Khan/khan-exercises — Issue #4432: Probability 1 - 1 is a prime number?
Author: KhanBugz
Created: 2011-10-16 18:10:41+00:00
State: open
Labels: firefox, vista

while in the module probability 1, I encountered a problem "A fair six-sided die is rolled. What is the probability that the result is prime? Write your answer as a simplified fraction." my answer to this was "2/3" which was simplified from 4/6, the number of prime number that are on a six sided die, over the number of number on a die. however this answer was not accepted, and when I went to look at the hints to see if I'd done something wrong, they said that the prime numbers were "2, 3, and 5" however this is incorrect, at least from what I've been taught thus far. since, at least from what I remember, according to the prime number video the number 1 is a prime number, because 1 is only divisible by 1 and itself.

[probability_1.html?seed=134&problem=1](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/probability_1.html?seed=134&problem=1&debug)

["2/3","2/3","2/3"]

Mozilla/5.0 (Windows NT 6.0; rv:7.0.1) Gecko/20100101 Firefox/7.0.1

MathJax is loaded, ready, queue length: 0