(1) fifteen coupons are numbered $\displaystyle 1,2,3,.......,15$.Seven Coupons are selected at random with replacement. Then find the probability no. appearing on a selected coupons is $\displaystyle 9$
(1) fifteen coupons are numbered $\displaystyle 1,2,3,.......,15$.Seven Coupons are selected at random with replacement. Then find the probability no. appearing on a selected coupons is $\displaystyle 9$
Then find the probability no. appearing on a selected coupons is 9
How many selected coupons?
What you have here is a binomial distribution with n = 7 and p = 1/15.
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