# Math Help - discrete math probability theory

1. ## discrete math probability theory

Discrete probability?
refer to a fair coin that is repeatedly flipped. If the coin is flipped 10 times, what is the probability of at most five heads.

what formula do I use to solve this and how do i know what formula to use?

I really need some help, I do not understand this at all

2. $\dbinom{10}{k}(0.5)^{10}$ is the probability of exactly k heads.

Now sum that $k=0\text{ to }5.$