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

$\red{\bigstar}$ 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