Khan/khan-exercises — Issue #10196: Probability 1 - Probability 1
Author: KhanBugz
Created: 2012-01-04 01:01:09+00:00
State: open
Labels: ipad, safari, wrong-or-unclear

Reporter: upland431@yahoo.com

A 6 sided dice is rolled. What fraction is prime.
My answer: 1,2,3,5 are prime ; 4 and 6 not. Therefore 4/6 which = 2/3 prime. The answer given is 1/2; failing to account for 1 as a prime number. I believe 1 is also both on the dice and is prime. So....????

[probability_1.html?seed=110&problem=1](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/probability_1.html?seed=110&problem=1&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/probability_1.html?seed=110&problem=1&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%222%2F3%5C%22%22%2C44%5D%2C%5B%22hint-activity%22%2C%220%22%2C3%5D%2C%5B%22hint-activity%22%2C%220%22%2C7%5D%2C%5B%22hint-activity%22%2C%220%22%2C10%5D%5D)

["2/3"]

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