Question

a man 3 times as old as his son . after 15 years , he will be only twice as old as his son . find their present ages.​

Answer 1

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$\sf{Given}\begin{cases}\sf{A\:man\:is \:3 \:times\:as\: old\: as \:his\: son.} \\ \sf{After \: 15 \: years \:he\: will \:be\: twice \:as \: old \:as \:his\: son.} \end{cases}$

Need To find:

• Their present ages =?

ExPlanation:

Let the age of son = x.

Then the age of man will be 3 times as old as his son = 3x.

After 15 years:

• Age of son = x + 15.
• Age of man = 3x + 15.

Given That:

• Man will be only twice as old as his son.

➠ 3x + 15 = 2(x + 15)

➠ 3x + 15 = 2x + 30

➠ 3x = 2x + 15

➠ x = 15.

ThereFore:

• The age of son = 15 years.
• The age of man = 45 years.

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Answer 2

Given

A man 3 times as old as his son . after 15 years , he will be only twice as old as his son .

To Find

Find the present ages

Solution

★ Let the present age of son's x and the man's be 3x

**According to the given condition**

• After 15 years
• Man's age = 3x + 15
• Son's age = x + 15

➠ 3x + 15 = 2(x + 15)

➠ 3x + 15 = 2x + 30

➠ 3x - 2x = 30 - 15

➠ x = 15

Hence,

Present age of Son = x = 15 years

Present age of Man = 3x = 45 years