If there are no failures in 5 trials, then there are 5 successes.
The probability of r successes in n trials is
[tex]C(n, r)p^r(1-p)^{n-r}[/tex] where p is the probability of success, n is the number of trials, and r is the number of successes. The C(n, r) is the number of combinations of n things taken r at a time, sometimes written [tex]_nC_r[/tex].
The probability you want is 0.00243 = 0.243% = 0.2% (rounded).
