Question

A coin is tossed 4 times, what is the probability of NOT getting 2 heads?

Answer 1

Use the complement method ...

Explanation:

P(not getting 2 heads) = 1 - P(getting two heads)

Assuming a FAIR coin and using the BINOMIAL distribution ...

P(getting two heads) `=(4!)/(2!xx2!)(1/2)^4=3/8`

Finally, ...

P(not getting 2 heads) `=1-3/8=5/8`

hope that helped