The probability of a consonant is 15/(21+15), and the probability of a vowel is 21/(21+15). The probability of drawing them in sequence (with replacement) is
p(sequence) = (15/36)(21/36) = (5/12)(7/12)
p(sequence) = 35/144
This problem has also been worked here.
p(sequence) = (15/36)(21/36) = (5/12)(7/12)
p(sequence) = 35/144
This problem has also been worked here.