Khan/khan-exercises — Issue #6199: Units - Rounding rule needs to be more specific
Author: KhanBugz
Created: 2011-11-13 06:03:38+00:00
State: open
Labels: chrome, xp

Reporter: scrubtub@thequeenofwands.com

I solved the problem: a rocket goes 38" per second; how far does it go in one minute? Round to the nearest thousandth.

The official answer is 190.
My answer was 190.02.
The problem is that dividing 38 by 12 results in a repeating decimal. I rounded the decimal to the nearest thousandth and got my answer. If I had used the number as it appeared on my calculator screen(with 29 '6s' and a 7 at the end), I would have gotten the "correct" answer. The protocol for dealing with very long or repeating decimals needs to be addressed as the answer for those with calculators will be different from those who are doing the calculations by hand (I assume some brave souls are doing it that way!), or for people like me who get hung up on details easily.
Thanks!
(and thanks for "Going Transonic" on my last problem - you guys are great!)

[units.html?seed=12&problem=english](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/units.html?seed=12&problem=english&debug)

["190.02"]

Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/15.0.874.106 Safari/535.2

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