There are a total of 60 white and red balls in the box. A ball in picked randomly. If the probability of picking a white ball is 2/5. How many red balls should be taken out so that the probability of picking white balls becomes 7/9 ? I am unable to crack this one.
2/5 * 60 = 24 There are 24 white and 36 red. Since does not have an integer solution, you cannot solve this by just removing red balls. If you remove red and white balls you can have 7/9, 14/18 or 21/27. (7 white and 2 red) or (14 white and 4 red) or (21 white and 6 red)
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