Khan/khan-exercises — Issue #14013: Kinematic equations - Rounding on kinematic equation
Author: KhanBugz
Created: 2012-02-16 20:31:14+00:00
State: open
Labels: chrome, other

Reporter: jwinder47@gmail.com

Using a calculator, without rounding until providing the final answer, i find a result of -1500.352, which i thought would round down (negatively) or up (absolutely) to -1500.4, but the required answer is given as -1500.3m [the equation is d = (18.2m/s)(13.6s)+1/2(-18.9m/s2)(13.6s)2]. i hesitate to say that -1500.3 is wrong, given the margin that might be allowed for rounding before all calculations had been performed; but i don´t see how -1500.4 would be wrong.

[kinematic_equations.html?seed=145&problem=accelerated](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/kinematic_equations.html?seed=145&problem=accelerated&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/kinematic_equations.html?seed=145&problem=accelerated&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5B%5B%5C%22-1500.4%5C%22%2C%5C%22m%5C%22%5D%5D%22%2C545%5D%2C%5B%22hint-activity%22%2C%220%22%2C5%5D%2C%5B%22hint-activity%22%2C%220%22%2C20%5D%2C%5B%22hint-activity%22%2C%220%22%2C124%5D%5D)

[[["-1500.4","m"]]]

Mozilla/5.0 (X11; Linux i686) AppleWebKit/535.11 (KHTML, like Gecko) Chrome/17.0.963.46 Safari/535.11

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