Question

If Ari, Ben, and Carol each choose a number at random between 1 and 5, inclusive, what is the probabilty that all of them choose different numbers?
(a) 1/125
(b) 1/25
(c) 1/5
(d) 3/5
(e) 12/25

Answer 1

The probability is\[
\frac{_5P_3}{5^3}=\frac{5\cdot4\cdot3}{5^3}
\]I'm sure you can work from there

Answer 2

thanks