Question

the present age of the father is four times that of his son . 20 years hence the age of father will be twice the age of the son . find their present ages with explanation

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Answer 1

Answer:

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Question 13

Q13)A man is four times as old as his son. After 20 years, he will be twice as old as his son at that time. Find their present ages.

Solution

Transcript

Solution :

Let the present age of the son = x years

Present age of the father = 4x years

After 20 years,

Son’s age will be (x + 20) years

and Father’s age will be (4x + 20) years

According to the condition,

4x+20=2(x+20)4x+20=2(x+20)

\Rightarrow\ 4x+20=2x+40⇒ 4x+20=2x+40

\Rightarrow4x-2x=40-20⇒4x−2x=40−20

2x=202x=20

⇒x=\frac{20}{2}⇒x=

2

20

⇒x=10⇒x=10

∴Present age of the son is10 years and

Present age of the father is = 4x=4\times10=404x=4×10=40 years.

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