Question

Mr. Jay has 100 pairs of shoes in his closet. He has 26 brown pairs, 12 navy pairs, 47 black pairs, and 15 white pairs. What is P(brown|black)?


Select an answer

A.
26/100+47/99


B.
26/100∙47/99


C.
47/100∙26/99


D.
26/100∙47/100

Answer 1

P(brown | black) = probability a shoe is brown given a black shoe was drawn first = 26/99.

None of the provided choices equals 26/99. (Choice C, 47/100∙26/99, is the joint probability P(black and brown), not the conditional probability.)