Correct Answer - Option 4 : 15, 7, 5
Given∶
Sum of the ages of friends = 3 years less than the Luv’s age
Three years ago, the sum of the ages of two friends = half of Luv’s age.
Formula Used∶
Concept of Linear Equations, Elimination Method
Calculation∶
Let Luv’s present age = x years
Sum of the ages of his two friends = y years
∴ y = x – 3
⇒ x – y = 3 ----(1)
3 years ago, Luv’s age = (x – 3) years
Sum of the ages of two friends = y - 3 - 3 = (y – 6) years
∴ (y – 6) = 1/2(x – 3)
⇒ 2y – 12 = x – 3
⇒ x – 2y = -9 ----(2)
Subtracting eq.(2) from (1), we get
y = 12
Putting y = 12 in eq. (1)
x – y = 3
⇒ x – 12 = 3
⇒ x = 3 + 12 = 15
Sum of friends age = 12 years
But they differ by 2 years, therefore,
Elder friend’s age = 7 years and Younger friend’s age = 5 years
∴ Luv’s present age is 15 years while age of his two friends is 7 years and 5 years.