Fifteen coupens are numbered `1,2,3,...15` respectively. Seven coupons are selected at random one at a time with replacement The Probability that the largest number appearing on a selected coupon is 9 is :

Fifteen coupons are numbered 1, 2, 3,…, 15 respectively. Seven coupons are selected random one at a time with replacement. The probability that the largest number appearing on the selected coupons is atmost 9, is :

Seven chits are numbered 1 to 7. Four chits are drawn one by one with replacment.The probability that the least number appearing on any selected chit is 5 is :

Three numbers are selected at random one by one with replacement from the numbers 1,2,3,….60. The probability that the A.M. of the numbers selected is 15 is.

Twenty coupons are numbered 1,2,3......,20 respectively.Four coupons are selected at random without replacement.If maximum and minimum numbers on selected coupons are 12 and 3 respectively.Then the probability that the maximum number on the remaining selected coupons is 9 is (1)(5)/(56) (2) (5)/(28) (3) (15)/(28) (4) (8)/(56)

Three numbers are selected from the set {1,2,3,...,23,24}, without replacement.The probability that the selected numbers form an A.P.is equal to