Question

a is thrice as old as b, 10 years ago he was four times as old as b. what are their present ages​

Answer 1

Given -

• a is thrice as old as b.
• 10 years ago he was four times as old as b.

To find -

• their present ages.

Solution -

As per the question, Presently,

a = 4b ----(i)

After 4 years, the relation between their age would be:

a + 4 = 3(b + 4) ----(ii)

Putting the value of a = 4b in (ii),

=> 4b + 4 = 3(b + 4)

=> 4b + 4 = 3b + 12

=> 4b - 3b = 12 - 4

=> b = 8 years.

To find the present age of a putting b = 8 in (i),

=> a = 4(8)

=> a = 32 years.

∴ The present age a is 32 years and b is 8 years.