Question

Arjun is twice as old as Shriya. Five years ago his age was three times Shriya's age. Find their present ages?​

Answer 1

Answer :

• Present ages of Shriya and Arjun are 10 years and 20 years respectively.

Given :

• Arjun is twice as old as Shriya. Five years ago his age was three times Shriya's age.

To Find :

• Their present ages.

Solution :

Let

• Present age Shriya = x years
• Present age of Arjun = 2x years

5 years ago

• Shriya's age = (x - 5) years
• Arjun's age = (2x - 5) years

It is given that

• Five years ago Arjun's age was three times Shriya's age.

According to question :

→ (2x - 5) = 3 (x - 5)

→ 2x - 5 = 3x - 15

→ - 5 + 15 = 3x - 2x

→ x = 10

Now

• Present age of Shriya = x = 10 years
• Present age of Arjun = 2x = 10(2) = 20 years

Hence, the present ages of Shriya and Arjun are 10 years and 20 years respectively.

Answer 2

Given :

• Arjun is twice as old as Shriya
• Five years ago his age was three times Shriya's age

To Find :

• Their present ages

Solution :

• Let the present age of Shriya be a years and that of Arjun be 2a years

• Now , 5 years ago :-

→ Age of Shriya = a - 5

→ Age of Arjun = 2a - 5

• According to the question :

$\:\:\:\:\implies \sf 2a\:-\:5\:=\:3(a\:-\:5)$

$\:\:\:\:\implies \sf 2a\:-\:5\:=\:3a\:-\:15$

$\:\:\:\:\implies \sf 3a\:-\:2a\:=\:15\:-\:5$

$\:\:\:\:{\red \star \: {\boxed{\sf{a\:=\:10}}}}$

$\:\:\bigstar\: \small {\sf{\underline{Present\:age\:of\:Shriya\:=\:a\:=\:10\:years}}}$

$\:\:\bigstar\: \small {\sf{\underline{Present\:age\:of\:Arjun\:=\:2a\:=\:2(10)\:=\:20\:years}}}$

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