## What-If 0022: "Cost of Pennies"

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peewee_RotA
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### What-If 0022: "Cost of Pennies"

“If you carry a penny in your coin tray, how long would it take for that penny to cost you more than a cent in extra gas?”
—Rob B

...

I find the conclusions tortured to make a joke, although the overall meat included a lot of considerations that I would have hoped for.

My issues:
#1 Valuing your time at $10/hr assumes that you are working for a wage 24/7. When factoring in things like cost of day care, this is useful. A stay at home parent can overcome the costs of daycare pretty easily except in extreme cases. That's a lot of money to save. However it is an offset of required expenditures, not money earned. There are *some* time based compensations that can be factored in. Owning a home business, especially one that produces products at home, pits time against money at all times of the day. If you're not filling orders, you're making sales to have orders to fill. This is great for etsy users, but the modern worker relies on 8 hour/day wage jobs. This is the exception. If I were to somehow make$10/hr every moment of my life outside of my day job, I would have to factor in the expenses, the time it takes to get between jobs, the cost of childcare for that, the strain it puts on family life. It's just an unrealistic assumption. It's not dollars over hours. It's dollars over impossible inconvenience.

#2 The loss of the time gained is not true if you were planning on that activity anyway. By the same calculations if I never picked up pennies but always read what-if then I do not have as much time in my life as if I always read what-if and always pickup pennies. I'm sure there's more to follow with this, but I don't want to waste more of my precious penny time on this forum post.
"Vowels have trouble getting married in Canada. They can’t pronounce their O’s."

Daimon
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### Re: What-If 0022: Cost of Pennies

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Last edited by Daimon on Thu Dec 06, 2012 6:47 pm UTC, edited 1 time in total.

EpicanicusStrikes
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### Re: What-If 0022: Cost of Pennies

"Well, one study suggests that 15 minutes of moderate exercise per day adds three years to your life expectancy."

Yes, because The Lancet has not degenerated into something willing to pull numbers out of its ass to support an arbitrary position. Plus those three years are at the end of my life, which are generally going to suck anyway. Why can't they just say that regular, sensible exercise can improve your health and the overall well-being/enjoyment of your life as it is? Why do they always need to play the mortality card?

Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

Klear
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### Re: What-If 0022: Cost of Pennies

When I find a small coin, I usually flip it. Heads, I take it, tails I throw it back for someone else to find it.

I never realized how ineffective that habit is =(

peewee_RotA
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### Re: What-If 0022: Cost of Pennies

EpicanicusStrikes wrote:Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

Actually you need exactly four more pennies to be lucky enough. The problem is that you're going to walk under a ladder on your way to get those pennies. So you have to ask yourself which force of luck is stronger, the four more or the ladder?
"Vowels have trouble getting married in Canada. They can’t pronounce their O’s."

Klear
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### Re: What-If 0022: Cost of Pennies

peewee_RotA wrote:
EpicanicusStrikes wrote:Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

Actually you need exactly four more pennies to be lucky enough. The problem is that you're going to walk under a ladder on your way to get those pennies. So you have to ask yourself which force of luck is stronger, the four more or the ladder?

Which penny should you pick up? The one where you have to go under a ladder, or the one where a black cat will have crossed your path?

mathmannix
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### Re: What-If 0022: Cost of Pennies

Klear wrote:
peewee_RotA wrote:
EpicanicusStrikes wrote:Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

Actually you need exactly four more pennies to be lucky enough. The problem is that you're going to walk under a ladder on your way to get those pennies. So you have to ask yourself which force of luck is stronger, the four more or the ladder?

Which penny should you pick up? The one where you have to go under a ladder, or the one where a black cat will have crossed your path?

You could always carry a pinch of salt, that's lighter than a penny. Then you could toss it over your shoulder to negate the ladder or cat negative luck!
I hear velociraptor tastes like chicken.

SerialTroll
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### Re: What-If 0022: Cost of Pennies

I believe Randall is using "calorie" where he should be using "Calorie". The capital "c" makes a difference of a factor of 1,000. I haven't fully read through the what-if to figure out if he is internally consistent or not. If he is, then he'd only need to fix the "c" issue. If not, his math is off.

YaleBreaker
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### Re: What-If 0022: Cost of Pennies

While the answer is obviously somewhat tongue-in cheek, I was also a bit irked by what appears to be the assumption that one earns 10 dollars an hour 24/7. I'll eat my words if I'm wrong, especially as I haven't done the math in my head, but that 3.6 number looks off.

But of course the larger issue is that Randall seems to have gotten it backwards. The value of time is not constant - except, ironically, when it comes to earnings.

Let's say our baseline job type is of the sitting-behind-a-desk-in-an-office-environment variety. But the office can neither meaningfully track the amount of time Homer (our average employee) spends working, nor in most cases can it reliably track his efficiency. It may be technically possible to monitor him via CCTV, but putting aside the Panopticon effect it would simply not be cost-effective.

The point is that, while Randall already made the mistake of generalizing, the irony is that he picked precisely the wrong sort of number as a ballpark figure: a fixed rate that is independent of one's use of time.

(Of course there is some minimum level of efficiency required to be eligible for a salary, but I think the point stands.)

Also, thinking about it, if we factor a fixed income into this, then we should factor in average expenditure as well. But again, to be fair, certain kinds of expenditures are time-sensitive, and some are not.

I think what it comes down to is this. Fixed income (i.e. a monthly salary) and fixed expenditure (i.e. rent) are unaffected by picking up a coin, barring exceptional circumstances (picking up a coin makes you just late enough for work to get fired, etc.).

There are non-fixed forms of income and expenditure. At college, I can spend a free half hour getting paid to do a cognitive science study. At a mall, I could spend a free minute buying a cone of ice cream. While picking up a coin is highly unlikely to cut into this sort of thing, I suppose it's conceivable that the time spent might conceivably accumulate across your history into some sort of systemic bias in your scheduling, butterfly effect-style.

This is really just a variation on calculating how much the nation saves on ink, printing costs, and time if we cut superfluous letters out of words (e.g. writing "bom" instead of "bomb" or "Return of the Jedi" instead of "Revege of the Jedi"). The difference being that a penny depends on much more nebulous factors.

A perhaps more fun variation on the topic is the maximum cost - i.e. property damage - you can realistically inflict with a penny.

rmsgrey
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### Re: What-If 0022: Cost of Pennies

A) It's far from given that someone can freely trade their time for money - for most people, picking up a penny represents the conversion of time, otherwise not convertible to money, to money.
B) The marginal utility of both time and money varies with how much you have of each - the more money you have, and the less free time in which to spend it, the lower the marginal utility of your money; the more free time you have, and the less money to spend in it, the lower the marginal utility of your free time. and in contemplating a given conversion method, you should also take account of how much you enjoy the activity the conversion involves...

five dollars
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### Re: What-If 0022: Cost of Pennies

The equation at the top is wrong - everything in the parenthesis should be the reciprocal of what he actually wrote. Oddly enough, he seems to have done the actual calculations using the correct equation, because if you just crunch the numbers he wrote as he wrote them, you do not get 140000 miles, you get a number much less than one with units of dollars squared per mile.

syrinxsean
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### Re: What-If 0022: Cost of Pennies

I'm blocked on the first formula, the one where Randall calculated the miles at which the weight of one penny would decrease mileage to the point where it would cost $0.01. I ran the following through Wolfram Alpha: "1 cent*((2.73 g / 50 lbs) * 0.5% * ($3.50/gallon))/30 miles/gallon". (Sorry for the lack of a URL. The phpBB software flagged it as spam when I included the direct URL.) The result was "4.363×10^-13 US dollars squared per meter"

This suggests that the units are just off, with the result being ($^2)/m, or "length^-1 * money^2. The answer units should just be m (length), so there's something wrong here. Wolfram Alpha's "Input interpretation" looks correct, so I'm not sure what's going on here. syrinxsean Posts: 7 Joined: Tue Nov 27, 2012 2:34 pm UTC ### Re: What-If 0022: Cost of Pennies five dollars wrote:The equation at the top is wrong - everything in the parenthesis should be the reciprocal of what he actually wrote. That's it! The "times" after the "1 cent" should be a "divide". That solves it. rml1997 Posts: 1 Joined: Tue Nov 27, 2012 2:55 pm UTC ### Re: What-If 0022: Cost of Pennies I read the article using my above average reading speed. I also did this at work, along with this comment, so the net effect has only been positive. My guilt for wasting works time, although I was waiting for outlook to sync, will make me more efficient so everyone gains SerialTroll Posts: 82 Joined: Mon Dec 20, 2010 5:28 am UTC ### Re: What-If 0022: Cost of Pennies five dollars wrote:The equation at the top is wrong - everything in the parenthesis should be the reciprocal of what he actually wrote. Oddly enough, he seems to have done the actual calculations using the correct equation, because if you just crunch the numbers he wrote as he wrote them, you do not get 140000 miles, you get a number much less than one with units of dollars squared per mile. You are quite right. If one only looks at the units you can see there is an error. You end up with cents * dollars as a unit instead of cents / dollars which cancels out after conversion. I'm expecting Randall to do his Orwellian fix soon. Klear Posts: 1965 Joined: Sun Jun 13, 2010 8:43 am UTC Location: Prague ### Re: What-If 0022: Cost of Pennies SerialTroll wrote: five dollars wrote:The equation at the top is wrong - everything in the parenthesis should be the reciprocal of what he actually wrote. Oddly enough, he seems to have done the actual calculations using the correct equation, because if you just crunch the numbers he wrote as he wrote them, you do not get 140000 miles, you get a number much less than one with units of dollars squared per mile. You are quite right. If one only looks at the units you can see there is an error. You end up with cents * dollars as a unit instead of cents / dollars which cancels out after conversion. I'm expecting Randall to do his Orwellian fix soon. 1 cent = OBEY! gladiolas Posts: 76 Joined: Tue Nov 06, 2012 1:41 am UTC ### Re: What-If 0022: Cost of Pennies I've enjoyed these, and I sent him some; how long should I expect to wait for a reply? And when should I assume he isn't going to use mine? Thanks. I can't think of anything to add to this pennies one. gmalivuk GNU Terry Pratchett Posts: 26822 Joined: Wed Feb 28, 2007 6:02 pm UTC Location: Here and There Contact: ### Re: What-If 0022: Cost of Pennies gladiolas wrote:I've enjoyed these, and I sent him some; how long should I expect to wait for a reply? And when should I assume he isn't going to use mine? Thanks. I can't think of anything to add to this pennies one. He likely has thousands of these backed up, and will get to whichever ones he finds most interesting/entertaining in whatever order he chooses. "We have no way of knowing", in other words, is the best answer to your questions. Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true. --- If this post has math that doesn't work for you, use TeX the World for Firefox or Chrome (he/him/his) peewee_RotA Posts: 504 Joined: Mon Dec 12, 2011 1:19 pm UTC ### Re: What-If 0022: Cost of Pennies gmalivuk wrote: gladiolas wrote:I've enjoyed these, and I sent him some; how long should I expect to wait for a reply? And when should I assume he isn't going to use mine? Thanks. I can't think of anything to add to this pennies one. He likely has thousands of these backed up, and will get to whichever ones he finds most interesting/entertaining in whatever order he chooses. "We have no way of knowing", in other words, is the best answer to your questions. If this is anything like a children show's mailbag, the questions are entirely made up and the e-mail address for sending questions is never checked. "Vowels have trouble getting married in Canada. They can’t pronounce their O’s." http://timelesstherpg.wordpress.com/about/ Angelastic Posts: 700 Joined: Thu Nov 03, 2011 8:36 am UTC Location: .at (let's see what's through here!) Contact: ### Re: What-If 0022: Cost of Pennies YaleBreaker wrote:A perhaps more fun variation on the topic is the maximum cost - i.e. property damage - you can realistically inflict with a penny. I bet it were a penny flying at 0.9c toward some typical Florida land, more than a penny would be lost in falling-cocaine-bale revenue. Knight Temporal, and Archdeacon of buttermongery and ham and cheese sandwiches. Nobody sells butter except through me. Smiley by yappobiscuits. Avatar by GLR, buffygirl, BlitzGirl & mscha, with cari.j.elliot's idea. Haiku Detector starts a trend to make way for my robot army. Klear Posts: 1965 Joined: Sun Jun 13, 2010 8:43 am UTC Location: Prague ### Re: What-If 0022: Cost of Pennies Angelastic wrote: YaleBreaker wrote:A perhaps more fun variation on the topic is the maximum cost - i.e. property damage - you can realistically inflict with a penny. I bet it were a penny flying at 0.9c toward some typical Florida land, more than a penny would be lost in falling-cocaine-bale revenue. Yeah, but it would cost a fortune to accelerate the penny to such speed, and you only have one penny... If you are really limited to just the one penny, I guess it would be best to just go around town and scratch all cars you can see. How long you can keep this up? I guess that depends on whether you count the inevitable need for food as expenses incurred on your property damage rampage. If so, you have time until you need to get some food/drink, I guess. If you go for expensive cars, you should be able to quite some damage this way. There might be some more efficient ways to do damage though. Maybe scratching something more expensive? Red Hal Magically Delicious Posts: 1445 Joined: Wed Nov 28, 2007 2:42 pm UTC ### Re: What-If 0022: Cost of Pennies It took me 24 seconds to post this ... Just my$0.02
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mania
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### Re: What-If 0022: Cost of Pennies

YaleBreaker wrote:While the answer is obviously somewhat tongue-in cheek, I was also a bit irked by what appears to be the assumption that one earns 10 dollars an hour 24/7.

That's not the assumption at all. If it were, one ought always pick up the penny as you're earning $10/hour either way - a penny gained then, is a penny gained. What he's done is concluded that someone that is willing to work for$10/hr likely values their time at not much less than that. If you then spend more than 0.01/10th of an hour picking up a penny, you've therefore made a poor economic decision given how you value your time.

A place you may argue this falls down is when un/underemployment is high, as it is today. Due to the stickiness of wages, you may find some people value their time at $10/hour but cannot find as many hours to work as they'd like. I still believe his argument holds though, as if you're unwilling to work for more hours at a lower wage, you oughtn't be willing to spend more than 0.01/10th of an hour picking up a penny either. keithl Posts: 662 Joined: Mon Aug 01, 2011 3:46 pm UTC ### Re: What-If 0022: Cost of Pennies Now, recalulate for Yap Island Rai Stone Money. peewee_RotA Posts: 504 Joined: Mon Dec 12, 2011 1:19 pm UTC ### Re: What-If 0022: Cost of Pennies Red Hal wrote:It took me 24 seconds to post this ... Just my$0.02

lol

mania wrote:
YaleBreaker wrote:While the answer is obviously somewhat tongue-in cheek, I was also a bit irked by what appears to be the assumption that one earns 10 dollars an hour 24/7.

That's not the assumption at all. If it were, one ought always pick up the penny as you're earning $10/hour either way - a penny gained then, is a penny gained. What he's done is concluded that someone that is willing to work for$10/hr likely values their time at not much less than that. If you then spend more than 0.01/10th of an hour picking up a penny, you've therefore made a poor economic decision given how you value your time.

A place you may argue this falls down is when un/underemployment is high, as it is today. Due to the stickiness of wages, you may find some people value their time at $10/hour but cannot find as many hours to work as they'd like. I still believe his argument holds though, as if you're unwilling to work for more hours at a lower wage, you oughtn't be willing to spend more than 0.01/10th of an hour picking up a penny either. I'm not sure you read any of the above arguments regarding the same point. Anyway I don't think you've really thought through your disagreement. In order to make your argument you still have to assume that you are or can make$10/hr 24/7. All you did was correct that the time picking up the penny wouldn't be included in the 24 hours.
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Klear
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### Re: What-If 0022: Cost of Pennies

peewee_RotA wrote:
Red Hal wrote:It took me 24 seconds to post this ...

Just my $0.02 lol mania wrote: YaleBreaker wrote:While the answer is obviously somewhat tongue-in cheek, I was also a bit irked by what appears to be the assumption that one earns 10 dollars an hour 24/7. That's not the assumption at all. If it were, one ought always pick up the penny as you're earning$10/hour either way - a penny gained then, is a penny gained.

What he's done is concluded that someone that is willing to work for $10/hr likely values their time at not much less than that. If you then spend more than 0.01/10th of an hour picking up a penny, you've therefore made a poor economic decision given how you value your time. A place you may argue this falls down is when un/underemployment is high, as it is today. Due to the stickiness of wages, you may find some people value their time at$10/hour but cannot find as many hours to work as they'd like. I still believe his argument holds though, as if you're unwilling to work for more hours at a lower wage, you oughtn't be willing to spend more than 0.01/10th of an hour picking up a penny either.

I'm not sure you read any of the above arguments regarding the same point. Anyway I don't think you've really thought through your disagreement. In order to make your argument you still have to assume that you are or can make $10/hr 24/7. All you did was correct that the time picking up the penny wouldn't be included in the 24 hours. The point isn't that with the$10/hour, you could make more money by working instead of picking up the penny, rather that picking up the penny gives you less money than the same time spent at work.

A better way to put it: Imagine somebody offers you a job consisting of repeatedly picking up pennies from the ground. What is the minimum wage you'd accept for this kind of work? If it is more than the worth of the pennies you'd pick up during your shift (no, you can't keep them in this line of work, you just pick them up), then picking up a penny on the sidewalk isn't worth your time.

Randall ballparked the minimum wage you'd accept as $10/hour, though that's definitely different for different people. For someone who earns millions, picking up pennies is not worth it in the same way as it is not worth it to him to get a poorly paid part-time job. mania Posts: 24 Joined: Sat Sep 20, 2008 9:44 am UTC ### Re: What-If 0022: Cost of Pennies peewee_RotA wrote:In order to make your argument you still have to assume that you are or can make$10/hr 24/7. All you did was correct that the time picking up the penny wouldn't be included in the 24 hours.

Nope, I'm also pointing out that even if you can't find more hours to work at $10/hr, it doesn't matter. That's how much you value your time. You could probably find more hours to work if you were only willing to lower your wage expectations down to the minimum wage, but you're not, and so therefore picking up a penny for >$0.01/$10 of an hour still fails to meet your time value. In fact, if you are able to work more hours (what you're saying Randall assumes), but you're choosing not to, that means you value your free time in excess of what you value your work time. You're not working that second job because you want the free time more than the minimum wage it would provide. At that, if you can make$10/hr 24/7 but are choosing not to, you absolutely should not be bending over to pick up that penny. Because it means you're spending more time working for a wage you've already decided is not worth working more hours for.

EDIT: I'll add though, this is obviously different if you were currently say waiting for a bus. In which case, picking up the penny was free. It's likewise very different if it means being late for a concert you've paid big money to attend. Or a flight. But - as a general approximation - I don't see any real fundamental problem in what Randall's done at all.

Klear
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### Re: What-If 0022: Cost of Pennies

Hey! I just realized that here in Czech Republic, the smallest coin is worth ~20 cents, and based on what I'm willing to work for right now (which is thankfully less than what I really earn), I have more than 40 seconds to pick up one crown. That's definitely worth my time.

Actually, picking up single crown in 3,3 seconds (I just tried it) gives you over 1000 crowns per hour, or around $56/hour. Seems like picking up coins is a lot more profitable here =) Eebster the Great Posts: 3484 Joined: Mon Nov 10, 2008 12:58 am UTC Location: Cleveland, Ohio ### Re: What-If 0022: Cost of Pennies Klear wrote:Hey! I just realized that here in Czech Republic, the smallest coin is worth ~20 cents, and based on what I'm willing to work for right now (which is thankfully less than what I really earn), I have more than 40 seconds to pick up one crown. That's definitely worth my time. Actually, picking up single crown in 3,3 seconds (I just tried it) gives you over 1000 crowns per hour, or around$56/hour. Seems like picking up coins is a lot more profitable here =)

But I would imagine there are many fewer Czech crowns per square meter than U.S. pennies. I expect there are a comparable number of crowns as there are quarters here, which is the better comparison.

teawithbuzz
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### Re: What-If 0022: Cost of Pennies

Randall miscalculated the energy required to pick up a penny for a 70 kg person raising their center of mass by 50 cm. He divided by efficiency instead of multiplying by efficiency, making the calculated value too large by a factor of 25. oops.

tomghc
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### Re: What-If 0022: Cost of Pennies

What about inflation? After all that mileage, the penny you picked up is worth a lot less than when you picked it up.

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### Re: What-If 0022: Cost of Pennies

That flow chart for picking up things reminded me of The Royal Society for Putting Things on Top of Other Things. Just saying.

"I cannot emphasize too strongly that there are many things not on top of other things!"
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KrishanuAR
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### Re: What-If 0022: Cost of Pennies

Pft, missed an opportunity to make it more awesome by accounting for inflation—or if not inflation, some metric that is tied to the price of gasoline as opposed to the price of an average good.

webgiant
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### Re: What-If 0022: Cost of Pennies

mathmannix wrote:
Klear wrote:
peewee_RotA wrote:
EpicanicusStrikes wrote:Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

Actually you need exactly four more pennies to be lucky enough. The problem is that you're going to walk under a ladder on your way to get those pennies. So you have to ask yourself which force of luck is stronger, the four more or the ladder?

Which penny should you pick up? The one where you have to go under a ladder, or the one where a black cat will have crossed your path?

You could always carry a pinch of salt, that's lighter than a penny. Then you could toss it over your shoulder to negate the ladder or cat negative luck!

I don't see where that would be lucky. It would take hours to pick up all the grains of salt so you'd have the pinch to throw over your shoulder later.

And you'd have to pick up all the grains of salt, otherwise you'd negate any increase in luck by the decrease in luck through spilling salt.

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### Re: What-If 0022: Cost of Pennies

SerialTroll wrote:I believe Randall is using "calorie" where he should be using "Calorie". The capital "c" makes a difference of a factor of 1,000. I haven't fully read through the what-if to figure out if he is internally consistent or not. If he is, then he'd only need to fix the "c" issue. If not, his math is off.
He does specify "food calorie", and food is always kilocalories, or Calories, so I'd say that's not actually a mistake.
Unless stated otherwise, I do not care whether a statement, by itself, constitutes a persuasive political argument. I care whether it's true.
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onetwothree4
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### Re: What-If 0022: Cost of Pennies

EpicanicusStrikes wrote:"Well, one study suggests that 15 minutes of moderate exercise per day adds three years to your life expectancy."

Yes, because The Lancet has not degenerated into something willing to pull numbers out of its ass to support an arbitrary position. Plus those three years are at the end of my life, which are generally going to suck anyway. Why can't they just say that regular, sensible exercise can improve your health and the overall well-being/enjoyment of your life as it is? Why do they always need to play the mortality card?

Someone also needs to factor in the missed luck for seeing a penny and not picking it up. Maybe that's the final piece of fortune I need to win the lottery. Can I really take the chance of ignoring it?

I read a really interesting article that suggested that beyond a certain point, people's life spans do not get meaningfully extended. So, assuming that you're a non-smoker, have a genetic predisposition for a 86 year life span, etc. these estimates of 'years gained' in life expectancy (due to exercise or other positive things) actually have less to do with extending your 'life span' in number of days lived and more to do with your 'health span'.
In short, you may not live 3 extra years by the extra exercise... but your last three years you will be healthy (not bed-ridden).

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### Re: What-If 0022: Cost of Pennies

keithl wrote:Now, recalulate for Yap Island Rai Stone Money.

Or Ningis.

teawithbuzz wrote:Randall miscalculated the energy required to pick up a penny for a 70 kg person raising their center of mass by 50 cm. He divided by efficiency instead of multiplying by efficiency, making the calculated value too large by a factor of 25. oops.

No. If the action is 20% efficient, then you need to use five times as much energy to do it, so dividing by 20% is the correct way to find out how much energy you need to use. If you wanted to find out how many coins you could pick up with a given amount of energy, then you'd multiply by 20%.

I wonder how many coins you could pick up if you converted the mass of a penny to energy.
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ijuin
Posts: 1148
Joined: Fri Jan 09, 2009 6:02 pm UTC

### Re: What-If 0022: Cost of Pennies

The fact that a cent is only worth a few seconds of time at any reasonable wage also implies that, if a cashier handles individual cents while making transactions and is not particularly quick about it, then the cashier's wages for the time spent handling the cents will eat up a sizable fraction of the value of the cents themselves. I have seen this used as one argument for merchants to price their items so that, when sales tax is included, the final total comes out to a multiple of 5 or 10 cents, since 1-2 cents' worth of wages is consumed just by handling the pennies at the cash register.

Beltayn
Posts: 92
Joined: Sat Oct 13, 2012 12:54 am UTC

### Re: What-If 0022: Cost of Pennies

ijuin wrote:The fact that a cent is only worth a few seconds of time at any reasonable wage also implies that, if a cashier handles individual cents while making transactions and is not particularly quick about it, then the cashier's wages for the time spent handling the cents will eat up a sizable fraction of the value of the cents themselves. I have seen this used as one argument for merchants to price their items so that, when sales tax is included, the final total comes out to a multiple of 5 or 10 cents, since 1-2 cents' worth of wages is consumed just by handling the pennies at the cash register.

I'd imagine that is made up for by the fact that customers are more likely to buy a whole extra item which costs $4.99 rather than$5.00

Eebster the Great
Posts: 3484
Joined: Mon Nov 10, 2008 12:58 am UTC
Location: Cleveland, Ohio

### Re: What-If 0022: Cost of Pennies

Angelastic wrote:I wonder how many coins you could pick up if you converted the mass of a penny to energy.

$\frac{2.73 g \cdot c^2}{410 cal} = 1.43 \times 10^9$

So over a billion anyway.