Question

kriti father age is 5 times as old as kriti. after 5 years ,father will be three times as old as kriti. find their present ages.​

Answer 1

Answer:-

$\red{\bigstar}$ Age of Kriti's Father $\large\leadsto\boxed{\tt\green{25 \: years}}$

$\red{\bigstar}$ Age of Kriti $\large\leadsto\boxed{\tt\green{5 \: years}}$

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• Given:-

• Kriti's father's age is 5 times as old as Kriti.

• After 5 years father will be three times in as old as Kriti.

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• To Find:-

• The present ages of Kriti and her father.

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• Solution:-

Let the age of Kriti's father be 'x' and that of Kriti be 'y'.

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Given that,

Kriti's father's age is 5 times as old as Kriti.

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Therefore,

➪ $\sf x= 5y \dashrightarrow\bf\red{[eqn.i]}$

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Also,

After 5 years father will be 3 times as old as Kriti.

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Therefore,

➪ $\sf x+5 = 3(y+5)$

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➪ $\sf x+5 = 3y + 15$

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➪ $\sf x - 3y = 15 - 5$

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➪ $\sf x - 3y = 10 \dashrightarrow\bf\red{[eqn.ii]}$

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• Substituting eqn.[i] in eqn.[ii]:-

➪ $\sf x - 3y = 10$

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➪ $\sf (5y) - 3y = 10$

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➪ $\sf 5y - 3y = 10$

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➪ $\sf 2y = 10$

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➪ $\sf y = \dfrac{10}{2}$

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★ $\large\underline{\underline{\bf\pink{y = 5}}}$

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• Substituting value of y in eqn.[i]:-

➪ $\sf x = 5y$

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➪ $\sf x = 5 \times 5$

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★ $\large\underline{\underline{\bf\pink{x = 25}}}$

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Therefore, the ages are:-

• Father = 25 years

• Kriti = 5 years

Answer 2

Answer:

Given :-

• Kriti father age is 5 times as old as kriti. After 5 years father age will be three times as old as kriti.

To Find :-

• What is their present ages.

Solution :-

» Let, the present age of kriti be x

» And, the present age of kriti's father will be 5x

➙ After 5 years ago,

Kriti 's age will be x + 5

And, the age of kriti's father will be 5x + 5

According to the question,

⇒ 5x + 5 = 3(x + 5)

⇒ 5x + 5 = 3x + 15

⇒ 5x - 3x = 15 - 5

⇒ 2x = 10

⇒ x = $\sf\dfrac{\cancel{10}}{\cancel{2}}$

➠ x = 5

Hence, the required ages are,

◪ Present age of Kriti = x = 5 years

◪ Present age of kriti's father = 5x = 5(5) = 25 years

$\therefore$ The present age of Kriti is 5 years and the present age of kriti's father will be 25 years .

Let's verify :-

↦ 5x + 5 = 3(x + 5)

Put x = 5 we get,

↦ 5(5) + 5 = 3(5 + 5)

↦ 25 + 5 = 15 + 15

↦ 30 = 30

➥ LHS = RHS

Hence, verified $\huge\green\checkmark$