Q. A basket contains 5 apples and 7 oranges and another basket contains 4 apples and 8 oranges. One fruit is picked out from each basket. The probability that the fruits are both apples or both oranges, is

A) 24/144
B) 56/144
C) 68/144
D) 76/144
Explanation

(d)
$P$ (selecting an apple from both baskets)
$= P$(apple from first basket) $\bullet P$(apple from second basket)
$= \frac{{\ ^{5}C}_{1}}{{\ ^{12}C}_{1}} \bullet \frac{{\ ^{4}C}_{1}}{{\ ^{12}C}_{1}}$
$P$ (selecting a orange from both baskets)
$= P$(orange from first basket) $\bullet P$(orange from second basket)
$= \frac{{\ ^{7}C}_{1}}{{\ ^{12}C}_{1}} \bullet \frac{{\ ^{8}C}_{1}}{{\ ^{12}C}_{1}}$
Required probability $= \frac{{\ ^{5}C}_{1}{\ ^{4}C}_{1}}{{\ ^{12}C}_{1}{\ ^{12}C}_{1}} + \frac{{\ ^{7}C}_{1}{\ ^{8}C}_{1}}{{\ ^{12}C}_{1}{\ ^{12}C}_{1}}$
$= \frac{20 + 56}{144} = \frac{76}{144}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.