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B. Statement 2 alone is sufficient.

1. P(W) = 2/5. This alone is not sufficient because we don't know anything about red and green ball probability.
2. P(G) = 1/3. This alone is sufficient because, probability of not drawing a green ball would be 1-P(G); and we know that the basket has only W, R and G balls. Therefore, probability of drawing a red or white ball will equal to probability of not drawing a green ball; which is equal to 1-P(G).
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Probability of selecting green ball = probability of selecting either white or red ball
Only B is sufficient
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Probability of choosing a ball that is red or white = 1-p(green).

Statement 2 is sufficient, my answer is B.
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A box contains only white balls, red balls and green balls. What is the probability of selecting a ball that is either red or white?

(1) The probability of selecting a white ball at random is 2/5

(2) The probability of selecting a green ball at random is 1/3



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MAGOOSH OFFICIAL SOLUTION:
Attachment:
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generis niks18 pikolo2510 amanvermagmat pushpitkc

Stumped by language in q stem.

A box contains only white balls, red balls and green balls. What is the probability of selecting a ball that is either red or white?

Quote:
(1) The probability of selecting a white ball at random is 2/5
OK, so all I need to find either probability of selecting a red ball or white ball.
Since P(white) ball is known from this option, why is this not suff.
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adkikani
generis niks18 pikolo2510 amanvermagmat pushpitkc

Stumped by language in q stem.

A box contains only white balls, red balls and green balls. What is the probability of selecting a ball that is either red or white?

Quote:
(1) The probability of selecting a white ball at random is 2/5
OK, so all I need to find either probability of selecting a red ball or white ball.
Since P(white) ball is known from this option, why is this not suff.

Hi adkikani

Statement 1: provides only the information about white ball, but we are asked to find the probability of either red or white. So in real life the probability of selecting either of the two items from among three items will always be higher than the probability of selecting only One item. Hence Statement 1 will not give you the complete probability.

In General OR means + in probability. so here you need to add the probabilities of red and white to get the final value.
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