Question 1078362
An urn contains 
7
white and 
6
green balls. Four balls are randomly drawn from the urn in succession, with replacement. That is, after each draw, the selected ball is returned to the urn. What is the probability that all 
4
balls drawn from the urn are white?
solution
total balls are=13
probability of white ball =7/13
balls are replaced  and 4 ball are drawn with replacement  every time probability of white ball will be =7/13
probability of all 4 balls are white =7/13x7/13x7/13x7/13=7x7x7x7/13x13x13x13
=2401/28561