### Instruction: Mahmoud tosses three coins. What is the probability that he will get at least one head?### Response: Hey Mahmoud, what's the probability that you flip three coins and get at least one head?
Well, what's the probability that we flip three coins and get no heads?
That would be $.5^3=.125$.
Yeah, and since that's the only other option, the probability that we flip three coins and get at least one head is $1-.125=.875$.