## Two clocks, one fast, one slow.

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### Two clocks, one fast, one slow.

You have two clocks which you set to the same correct hour and start running at the same time. One clock gains a minute every hour; the other loses a minute every hour. Which clock will be correct more often?

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- closed-minded spiritualist
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### Re: Two clocks, one fast, one slow.

**Spoiler:**

I'm looking forward to the day when the SNES emulator on my computer works by emulating the elementary particles in an actual, physical box with Nintendo stamped on the side.

"With math, all things are possible." —Rebecca Watson

"With math, all things are possible." —Rebecca Watson

### Re: Two clocks, one fast, one slow.

Huu this one was fun

**Spoiler:**

### Re: Two clocks, one fast, one slow.

I decided to assume the clocks are 24-hour clocks, so we can use the word "day" instead of "12-hour period". It doesn't fundamentally change the answer.

(Also, I of course assumed that the hands of the clocks move continuously and uniformly -- we're not talking about clocks that keep perfect time for a while and then suddenly "jump" forward or back.)

Let's say that in addition to the fast clock and the slow clock, we have a third, perfectly accurate, clock in the same room.

EDIT: By the way, a brief remark about the psychology or pedagogy behind this puzzle:

(Also, I of course assumed that the hands of the clocks move continuously and uniformly -- we're not talking about clocks that keep perfect time for a while and then suddenly "jump" forward or back.)

Let's say that in addition to the fast clock and the slow clock, we have a third, perfectly accurate, clock in the same room.

**Spoiler:**

EDIT: By the way, a brief remark about the psychology or pedagogy behind this puzzle:

**Spoiler:**

### Re: Two clocks, one fast, one slow.

Heh. I guess the answer truly lies in what is the "right" time. What is the frame of reference and what is its relative velocity expressed as a percentage of the speed of light in a perfect vacuum (for the purpose of calculating time dilation)? Do the clocks gain and lose a minute from the "correct" time, or from one another? Are the clocks analog or digital, and are they reliant on the same power source? Does [imath]\pi = 4[/imath]?

Ultimately, the answer is:

Ultimately, the answer is:

**Spoiler:**

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