SOLUTION: An urn contains 40 balls. Some are red balls and the rest are white balls. If the probability of extracting a white ball is 0.675, how many white balls are there? How do I

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Question 911536: An urn contains 40 balls. Some are red balls and the rest are white balls.
If the probability of extracting a white ball is 0.675, how many white balls are there?

How do I do this question? Help please.
Thank you.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
An urn contains 40 balls. Some are red balls and the rest are white balls.
If the probability of extracting a white ball is 0.675, how many white balls are there?
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Use a proportion::
x/40 = 675/1000
x = 40*0.675
x = 27
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Cheers,
Stan H.
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