Number System
Three numbers are in ratio of 3: 4 :5. If the sum of first & third numbers is more than second number by 52, which will be largest number?
Let the present age of the father be 'x' and that of the son be 'y'. Then x/y = 8/3∴ 3x = 8y Further, x + 12/y + 12 = 2/1 ∴ x + 12 = 2y + 24 ∴ x - 2y = 12 ......(ii)From eqn (i) and (ii), x = 48, y = 18 ∴ sum = 66 yrs.
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.