Question

5 years ago, A was thrice as old as B and 10 years later. A shall be twice as old as B . what are the present ages of A and B?

Answer 1

Heya!

Let the age of A be x years and B be y years.

Then, ATQ,

Five years ago :
x - 5 = 3 (y-5)
x - 5 = 3y - 15
x - 3y = -10 (i)

Ten years later :
x + 10 = 2 (y + 10)
x + 10 = 2y + 20
x - 2y = 10 (ii)

Subtracting both the equations,
x-3y = -10
x-2y = 10
which is, y = 20

Now finding x,
x - 2y = 10
x - 40 = 10
x = 10 + 40 = 50

Therefore, A's age is 50 years while B's age is 20 years

Hope it helps!