Homework Help: Two coin are tossed 4 times ,find?

1. May 8, 2010

mattamimi

1)the probability of 2 heads in 4 times ?
2)the probability of less than one head once?
3)the probability of more than 2 tails in 3 times ?
4)the expected number of two tails ?
5)the variance of the number of 2 heads

2. May 8, 2010

Staff: Mentor

What have you tried?

3. May 8, 2010

Redbelly98

Staff Emeritus
Last edited: May 8, 2010