NCHMCT JEE 2015 Question Paper with solutions for online practice

Let, present age of Puja = x years
and present age of Sunita = y years 3 years ago,
x - 3 = $\frac{1}{4}$ (y - 3)
⇒ 4x – 12 = y – 3
⇒ 4x – y = 9 ...(i)
After 3 years, $\frac{\mathit{x}+3}{\mathit{y}+3}$ = $\frac{7}{22}$
⇒ 22x + 66 = 7y + 21
⇒ 22x – 7y = –45 ...(ii)
4x – y = 9 ] × 7
22x – 7y = –45 ] × 1
28x – 7y = 63
22x – 7y = –45
6x = 108 ⇒ x = 18
Putting the value of x in (i)
4x – y = 9
⇒ 4(18) – y = 9
⇒ 72 – 9 = y
⇒ y = 63
Hence, the present age of Sunita = 63 years.