I was hoping someone might check my work as the answer seems a little off:

A die is thrown 20 times and a success id defined as a one or a six on the upface of the die.

Use the binomial distribution to determine the probability of getting exactly five successes in the 20 trials.

I came up with:

C(20,5)*((2/6)^5)*((4/6)^15)

=0.1462

Any help would be appreciated.