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The current ages of Sonali and Monali are in the ratio 5 : 3. Five years from now, their ages will be in the ratio 10 : 7. Then Monali's current age is = ?

13 years
25 years
39 years
415 years

Answer:- 1

Explanation:-

Solution:

Let,
⇒ Sonali's age = 5x
⇒ Monali's age = 3x
According to the question,

\begin{aligned} \Rightarrow \frac{5 x + 5}{3 x + 5} = \frac{10}{7} \\ \Rightarrow \frac{x + 1}{3 x + 5} = \frac{2}{7} \\ \Rightarrow 7 x + 7 = 6 x + 10 \\ \Rightarrow x = 3 \end{aligned}

$\eqalign{ & \Rightarrow \frac{{5x + 5}}{{3x + 5}} = \frac{{10}}{7} \cr & \Rightarrow \frac{{x + 1}}{{3x + 5}} = \frac{2}{7} \cr & \Rightarrow 7x + 7 = 6x + 10 \cr & \Rightarrow x = 3 \cr}$ ⇒ So, Monali's present age = 3x
= 3 × 3 = 9 years

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⇒ So, Monali's present age = 3x
= 3 × 3 = 9 years ", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

Let,
⇒ Sonali's age = 5x
⇒ Monali's age = 3x
According to the question,

\begin{aligned} \Rightarrow \frac{5 x + 5}{3 x + 5} = \frac{10}{7} \\ \Rightarrow \frac{x + 1}{3 x + 5} = \frac{2}{7} \\ \Rightarrow 7 x + 7 = 6 x + 10 \\ \Rightarrow x = 3 \end{aligned}

$\eqalign{ & \Rightarrow \frac{{5x + 5}}{{3x + 5}} = \frac{{10}}{7} \cr & \Rightarrow \frac{{x + 1}}{{3x + 5}} = \frac{2}{7} \cr & \Rightarrow 7x + 7 = 6x + 10 \cr & \Rightarrow x = 3 \cr}$ ⇒ So, Monali's present age = 3x
= 3 × 3 = 9 years ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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