Question

Ahmed's father is thrice as old as Ahmed. After 12 years, his age will be twice that if his son. Find their present age

Answer 1

ANSWER WITH FULL EXPLANATION

Let the present age of Ahmed be $x$ years. 
Present age of Ahmed's father = $3x$ years

After 12 years
Age of Ahmed = $(x+12)$ years
Age of Ahmed's father = $(3x+12)$ years

ATQ (According To question)
After 12 years,
Age of father = Twice the age of son
⇒ Age of father = 2 × Age of son
⇒ $(3x+12)=2(x+12)$
⇒ $3x+12=2x+24$
⇒ $3x+12-2x=2x+24-2x$    [Subtracting $2x$ from both sides. ]
⇒ $3x-2x+12=2x-2x+24$
⇒ $x+12=24$
⇒ $x+12-12=24-12$    [Subtracting 12 from both sides. ]
⇒ $x=12$

Present age of Ahmed = $x$ years = 12 years
Present age of Ahmed's father = $3x$ years = (3 × 12) years = 36 years

∴ The present age of Ahmed is 12 years and the present age of Ahmed's father is 36 years. 

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