A permutation of 5 letters is formed from the letters O, P, Q, R, S, T and U with no
repetitions. How many permutations
a) begin with the letter R?
b) end in a vowel?
c) have the letters Q and U in adjacent positions?
A permutation of 5 letters is formed from the letters O, P, Q, R, S, T and U with no
repetitions. How many permutations
a) begin with the letter R?
If the first letter is an R, the second can be any of the remaining 6,
the third any of the now remaining 5, the fourth any of the now remaining 4,
and the fifth any of the now remaining 3, for a total of: 6x5x4x3=360.