Q. A box contains three blue marbles, five red marbles, and four white marbles. If one marble is drawn at random, find:(adsbygoogle = window.adsbygoogle || []).push({});

a) P(blue|not white)

b) P(not red|not white)

The answer for both a) and b) is 3/8.

However right now I don't even understand the question.

part a) wants possibility of getting a blue ball given that white wasn't drawn.

So... NOT getting a white ball is 8/12.

Given that, getting a blue ball is 3/11.

but 3/11 is not even close to 3/8!

What's wrong with my work?

Thanks in advance!

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# Homework Help: Conditional probability marble question

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