manojgmat wrote:

Each of the 25 balls in a certain box is either red , blue or white and has a number from 1 to 10 painted on it. if one ball is to be selected at randon from the box , what is the probalility that the ball selected will either be white or have an even number painted on it.

1. the probability that the ball will both be white and have an even number painted on it is 0.

2. thet probability that the ball will both be white minus that the ball will have an even number painted on it is 0.2.

So we need to know the probability of a white ball drawn and the probability of an even number drawn.

1. so that's telling us there are NO EVEN WHITE BALLS. INSUFF since we dont know the even balls or white balls numbers

2. ProbW - ProbEven = .2

we dont know the probability of even balls OR white ball drawn so 2 unknowns INSUFF

Combined:

No even white balls doesnt help use derive ProbW or ProbEven so INSUFF

E.

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