Khan/khan-exercises — Issue #6363: Prime factorization - Prime factorisation - practice problem says answer is wrong
Author: KhanBugz
Created: 2011-11-15 11:33:03+00:00
State: open
Labels: win7, wrong-or-unclear

Reporter: richie_hopaneng@hotmail.com

Question is: Find prime factorisation of 75.
This was a recap of an exercise I did a while ago, so I watched the video to refresh my memory as to what it was.
The video showed how to factorise 75, to which it is showed that the answer is 3x5x5, which can also be written as 3x5^2.

The exercise says this is wrong.
And even showing the answer, the exercise comes to the conclusion that 75 is factorised to 3x5x5.

[prime_factorization.html?seed=180&problem=composite](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/prime_factorization.html?seed=180&problem=composite&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/prime_factorization.html?seed=180&problem=composite&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%223x5%5E2%5C%22%22%2C280%5D%2C%5B%22hint-activity%22%2C%220%22%2C6%5D%2C%5B%22hint-activity%22%2C%220%22%2C7%5D%2C%5B%22hint-activity%22%2C%220%22%2C7%5D%2C%5B%22hint-activity%22%2C%220%22%2C8%5D%2C%5B%22hint-activity%22%2C%220%22%2C8%5D%5D)

["3x5^2"]

Opera/9.80 (Windows NT 6.1; U; en) Presto/2.9.168 Version/11.52

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