Two balls are drawn in succession without replacement out of

Two balls are drawn in succession, without replacement, out of a box containing 2 red and 5 white balls. What is the probability that the second ball drawn is red given that the first ball drawn is white?

A.) 1/3

B.) 1/21

C.) 10/21

D.) 5/21

Solution

total balls = 2R+5W = 7

probability that the second ball drawn is red given that the first ball drawn is white=

Prob. of first ball white * Prob of second ball red = (5/7)* (2/6) = 10/42 = 5/21

Answer is \'D\'