This question was previously asked in

DSSSB JE EE 2019 Official Paper (Held on 5 Nov 2019)

Option 4 : 50 years

**Calculation:**

Let the present age of man be x years

10 years ago,

Man age be (x - 10) years

10 years after,

Man age be (x + 10) years

According to the question:

125% of (x - 10) = \(83\dfrac{1}{3}{\%}\) of (x + 10)

⇒ (125/100)( x - 10) = (250/300)(x+10)

⇒ (5/4)(x - 10) = (5/6)(x + 10)

⇒ (x - 10)/4 = (x + 10)/6

⇒ 6(x - 10) = 4(x + 10)

⇒ 6x - 60 = 4x + 40

⇒ 6x - 4x = 40 + 60

⇒ 2x = 100

⇒ x = 100/2 = 50 years

**∴ Present age of the man is 50 years.**

__Alternate Method__

**Calculation:**

Let the age before 10 years be x years

According to the question:

125x/100 = x + 10

⇒ 5x/4 = x + 10

⇒ 5x = (x + 10) × 4

⇒ 5x = 4x + 40

⇒ 5x – 4x = 40

⇒ x = 40

Present age = x + 10 = 10 + 40 = 50

∴ Present age of the man is 50 years.