Question

Present age of rekha and reshma are in ratio 3 ratio 4 5 year from now the ratio of their ages will be 4ratio
5 find their present age

Answer 1

Answer:

Age of Rekha = 15yrs.

Age of reshma = 20yrs.

Step-by-step explanation:

>> Given that the present ratio of their ages are 3:4. Story further tells that after 5 years ratio becomes 4:5.

>> TARGET is to find the present ages of these two people.

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So, for our convenience, let's assume the present age of Rekha and Reshma as 3x and 4x.

Now, fast forward after 5 yrs, what would be the present age? present age + 5.

So, Rekha's present age = 3x + 5

Reshma's present age = 4x +5

What else we know? We know that at this time the ratio becomes 4:5. What does that means?

It means that::

$\bf \implies \dfrac{3x+5}{4x+5} = \dfrac{4}{5}$

Let's do a cross multiplication here;

$\sf \implies 5(3x+5) = 4(4x+5)$

$\sf \implies 15x + 25 = 16x +5$

Variables on the left side,and constants on the right!

$\sf \implies 15x -16x = 20-25$

$\implies \sf -x = -5$

Negatives will get cancelled of both the sides.

As earlier assumes:

Age of Rekha = 3x = 3×5 = 15 yrs.

Age of Reshma = 4x = 4×5 = 20 yrs.

Answer 2

Answer:

Given :-

• Present age of Rekha and Reshma are in the ratio of 3:4.
• After 5 years the ratio of their ages will be 4:5.

To Find :-

• What is their present ages.

Solution :-

» Present age ratio= 3:4

» And, after 5 years ratio = 4:5

» Let, present age of Rekha is 3x

» And, the present age of Reshma is 4x

After 5 years,

↦ Present age of Rekha = 3x + 5

↦ Present age of Reshma = 4x + 5

➣ According to the question,

⇒ $\dfrac{3x + 5}{4x + 5}$ = $\dfrac{4}{5}$

【 By doing cross multiplication 】

⇒ 5(3x + 5) = 4(4x + 5)

⇒ 15x + 25 = 16x + 20

⇒ 15x - 16x = 20 - 25

⇒ - x = - 5

➠ x = 5 years

Hence, their required ages will be,

✦ Present age of Rekha = 3x = 3(5) = 15 years

✦ Present age of Reshma = 4x = 4(5) = 20 years

$\therefore$ The present age of Rekha is 15 years and the present age of Reshma is 20 years .

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