# Math Help - Binomial distribution.

1. ## Binomial distribution.

XYZ has calculated the probability that a customer who comes into the store and buys something is 0.20. Inthe course of a certain day 50 customers visit the store. Calculate the probability that 10 or fewer customers make a purchase on this particular day.

More important for me is result than the formula.

2. Originally Posted by Suchy
XYZ has calculated the probability that a customer who comes into the store and buys something is 0.20. Inthe course of a certain day 50 customers visit the store. Calculate the probability that 10 or fewer customers make a purchase on this particular day.

More important for me is result than the formula.
X ~ Binomial(n = 50, p = 0.20).

Calculate $\Pr(X \leq 10)$.