NIELIT 2017 July Scientist B - Section A: 5

Question

The present ages of three persons in proportions $4 : 7 : 9$. Eight years ago, the sum of their ages was $56$. Find their present ages (in years).

• A. $8, 20, 28$
• B. $16, 28, 36$
• C. $20, 35, 45$
• D. None of the above options

Answer 1

Assume their age ratio is $x$

then age of 3 person is $4x$,$7x$ ,$9x$

According to the question,$8$ year ago the sum of their age was $56$

$\Rightarrow (4x-8)+(7x-8)+(9x-8)=56$

$\Rightarrow 20x-24=56$

$\Rightarrow 20x=80$

$\Rightarrow x = 4$

Now their present age is $16,28,36$, Option B.