LCM of 10, 15, 25 = 150When we drive 2641 by 150 the remainder is 91.But the remainder should be 7.So, the number to be subtracted from 2641 is 91 - 7 = 84.
Let the father's age be x and son's age yTherefore, x + y = 60 ....................(i)Five years back, (x - 5) = 4 (y - 5)x - 4y = - 15 ......................(2)Solving (1) and (2), x = 45 and y = 15
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