Math
posted by Star K .
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:
(a) With replacement ____________ (b) Without replacement ______________

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