Let the no. be xTherefore 68x / 100 - 35x / 100 = 1216 Therefore x = 1216 x 100 / 33Therefore 28% of x = 28x / 100 = 1216 x 100 / 33 x 28 / 100= 1216 x 100 x 28 / 33 x 1/100 = 1031.75
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.