Shamika E. answered • 12/26/19

Tutor, problem solver, puzzler, math lover and accountant

The probability of X successes in Y trials in which the probability of success in any trial is Z% is calculated as based on the product of:

(1) the number of combinations of success,

(2) percentage of success^number of successes,

(3) percentage of failures^number of failures

Formula: YCx x (Z%)^X x (1-Z%)^(Y-X)

: 7C3 x (0.35)^3 x (0.65)^4

: 7!/3!4! x (0.35)^3 x (0.65)^4

: 35(0.35)^3(0.65)^4

Answer = 26.8%