A box contains four red marbles, seven white marbles, and five blue marbles. If two marbles are drawn one at a time, find the probability that both marbles are white if the draws are made as follows:

Question

(a) With replacement ____________ (b) Without replacement ______________

Answer 1

There is a total of 16 marbles and 7 are white.

With replacement: (7/16)*(7/16) = 49/256 = 0.1914

Without replacement: (7/16)*(6/15) = 42/240 = 7/40 = 0.1750