Number System
The difference between the two digit number and the number obtained by interchanging its digits is 54. The difference between the digits is?
If the sum of the digits of a number is divisible by 9, the number will be divisible by 9.2 + 6 + 3 + 2 + 5 + 1 = 19The nearest multiple of 9 is 18.19 - 18 = 1.
Let Radha's present age = x years.∴ x = 2 (x = 12) - 3= x = 2x - 24 - 3= x = 27∴ Raja's present age = 4/9 x 27= 12 years ∴ Raja's age after 5 years = 12 + 5 = 17 years
Let the middle digit be x. Then, 2x = 10 or x = 5.So, the number is either 253 or 352. Since the number increases on reversing the digits, so the hundred's digit is smaller than the unit's digit. Hence, required number = 253.
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
EXAMIANS