Answer:
Present age = 10
Explanation:
Let us assume that,
→ Present age = x
Forming the equation,
→ x + 10 = 4(x - 5)
Now the value of x will be,
→ x + 10 = 4(x - 5)
→ x + 10 = 4x - 20
→ x - 4x = -20 - 10
→ -3x = -30
→ x = -30/-3
→ x = 30/3
→ [ x = 10 ]
Hence, the boy's age is 10.