Question

The present age of the father is 20 years more than that of the son.After three years ratio of a age of the son and the father becomes 19:39 . then find the present age of the son.​

Answer 1

Given :-

• The present age of the father is 20 years more than that of the son.
• After three years ratio of a age of the son and the father becomes 19:39 .

To Find :-

• Find the present age of the son.

Solution :-

~Here, firstly we’ll assume the present ages of father and son, then we will frame an equation according to the conditions given. By solving that equation we can find the required answer.

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• Let the age of the sone be ‘x’ years
• Then the age of  father will be ‘x+20’ years

According to the question :-

$\sf \implies \dfrac{x+3}{x+20+3} = \dfrac{19}{39}$

$\sf \maltese \;\; \bigg\{ Cross\;multiply \bigg\}$

$\sf \implies 39( x + 3) = 19( x + 23 )$

$\sf \implies 39x + 117 = 19x + 437$

$\sf \implies 39x -19x = 437 -117$

$\sf \implies 20x = 320$

$\boxed{\bf{ \bigstar \;\;\; x = 16 }}$

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Therefore,  

• Present age of the son is 16 years

 

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Answer 2

Question :-

The present age of the father is 20 years more than that of the son.After three years ratio of a age of the son and the father becomes 19:39 . then find the present age of the son.

Answer :-

• Let the age of the sone be ‘x’ years
• Then the age of father will be ‘x+20’ years

According to the question :-

$\sf \implies \large \frac{x + 3}{x + 20 + 3} = \frac{19}{39}$

⟹ 39(x+3) = 19(x+23)

⟹ 39x + 117 = 19x + 437

⟹ 39x − 19x = 437 − 117

⟹ 20x = 320

x = 16

Therefore, present age of the son is 16 years.