dtweah wrote:The probability of picking an apple from a basket is .25 and that of picking a rotten fruit is .50. The probability of picking a rotten apple is .14. Find the prob that neither an apple nor a rotten fruit is picked.
A. .75
B. .39
C. .25
D. .5
E. .61
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Hi!
Even if we're stumped by the math, we can immediately eliminate 3 of the 5 choices and then eliminate a 4th.
Since the probability of picking a rotten fruit is .5, even if there were no apples the probability of choosing a non-rotten fruit would be .5. Since there are apples, and not all of them are rotten, the answer must be less than .5 - eliminate A, D and e.
There's a .25 chance of picking an apple. If there were no overlap between apples and rotten, then there would be a .75 (.5 + .25) chance of picking an apple or rotten, giving us a .25 (1 - .75) chance of picking neither apple nor rotten. Since there is some overlap, there must be a greater than .25 chance of drawing rotten or apple.
So, the answer must be greater than .25 - eliminate C.
Only B remains!
