Probability Help

Question

An unbiased coin is tossed five times. Find the probability of the given event.

The coin lands heads at least once.

Answer 1

at least once means 1,2,3,4 or 5 times

 

lets calculate that it never lands on H and subtract from 1 since this is the complement.

 

0 heads = 

 

T T T T T

 

(1/2)^5  = 1/32

 

Therefore our answer is 1- 1/32 = 31/32