Let the numbers be x, x + 2, x + 4, x + 6, and x + 8Avg = x + x + 2 + x + 4 + x + 6 + x + 8/5 = 40Therefore, 5x + 20 = 200Therefore, x = 180/5 = 36Therefore, r = x + 4 = 40 s = x + 6 = 42Therefore, Product = 1680
Since the number is greater than the number obtained on reversing the digits, so the ten's digit is greater than the unit's digit.Let the ten's and unit's digits be 2x and x respectively.Then, (10 * 2x + x) - (10x + 2x) = 369x = 36x = 4Required difference = (2x + x) - (2x - x) = 2x = 8.
Two balls can be drawn from 18 balls in 18C2 Ways, ie 153 ways. One white from 8 white balls can be drawn in 8C1 = 8 ways and one black ball from 10 black can be drawn in 10C1 = 10 ways.∴ n(S) = 153, n(E) = 8 x 10 = 80∴ P(E) = 80/153