Question

find his present age?

Answer 1

let the present age of Mr. Pratap be X yrs.
His age after 40 yrs would be (X+40) yrs.
His age 32 yrs ago was (X-32) yrs.
So, Mr. Pratap's age, X > 32. 
From the question, (X+40) = (X-32)²
=> X + 40 = X² + 1024 - 64X
X² - 65X + 984 = 0
X² - 41X - 24X +984 =0
X(X - 41) - 24(X - 41) = 0
(X - 41) (X - 24) = 0
=> X = 41 (or) 24
but, if X = 24, then X < 32. So, it is rejected.
Hence the age of Mr. Pratap is 41 years.
Hope my answer helps you.