Let me see if I can recall my biz school stats class.

This is a binomial. You need 5 successes in 7 tries with a 60% chance of success on any given try. Correct?

Okay then so the insane gorilla fomula is trail is p, k is success, n is number of trials.
= n!/ [(n-k)! k!] * p^k * (1-p)^n-k

= 7!/(7-5)! 5! * (0.6)^5 (1-.6)^(7-5).

=5040/(2)(120) * (.0778)(.16)

= 21* .0124

=2614 or 26%

So with any given trial having a 60% chance of success, you'll only see 5 successes in 7 trials 26% of the time.

5 for 5 would be

5!/[(5-5)! 5! * (0.6)^5 (1-.6) ^(5-5)

=120/120 * .6^5 * (1-.6)^0

= .6^5 or 7.78%

Of course, its easier since its 5 for 5 to just take .6 times .6 5 times.