Number System
A bag contains eighteen 25-paise coins, seventeen 50-paise coins, twentytwo one-rupee coins, nine 2-rupee coins and three 5-rupee coins. What is the total amount in the bag (Ans in rupees) ?
Total balls = 5 + 4 + 4 = 13∴ n(S) = 13C3 = 2862 blue balls can be selected from 4 balls in 4C2 = 6 ways and the remaining one ball is to be selected from 9 balls in 9C1 = 9 ways ∴ n(E) = 6 x 9∴ P(E) = 6 x 9/286 = 27/143