Question

plzz ans guys very important

The present ages of A and B are in the ratio of 7:9. After 5 years the ratio of their ages will be 4:5 .Find their present ages

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Answer 1

Answer:

A is 35 years old and B is 45 years old.

Step-by-step explanation:

Given :

Present Ages of A and B are in ratio 7 : 9

After 5 years ratio of their ages will be 4 : 5

To Find :

Their present ages

Solution :

✯ $\textbf{\small{\underline{Consider the present Ages as -}}}$

• A as 7x
• B as 9x

$\rule{300}{1.5}$

✯ $\textbf{\small{\underline{Ages after 5 years -}}}$

• A --> (7x + 5) --> 4
• B --> (9x + 5) --> 5

$\rule{300}{1.5}$

★ $\boxed{\tt{\frac{(7x + 5)}{(9x + 5)} = \frac{4}{5}}}$

$\tt{\longrightarrow} \: \dfrac{(7x + 5)}{(9x + 5)} = \dfrac{4}{5}$

$\tt{\longrightarrow} \: 5(7x + 5) = 4(9x + 5)$

$\tt{\longrightarrow} \: 35x + 25 = 36x + 20$

$\tt{\longrightarrow} \: 36x - 35x = 25 - 20$

$\tt{\longrightarrow} \: x = 5$

$\rule{300}{1.5}$

★ Value of 7x

$\tt{\longrightarrow} \: 7(5)$

$\tt{\longrightarrow} \: 35$

A is presently 35 years old.

$\rule{300}{1.5}$

★ Value of 9x

$\tt{\longrightarrow} \: 9(5)$

$\tt{\longrightarrow} \: 45$

B is presently 45 years old.

$\therefore$ A is 35 years old and B is 45 years old.

Answer 2

Answer:

The present Ages of A and B are 35 and 45 respectively.

Step-by-step explanation:

Gívєn -

The present ages of A and B are in the ratio of = 7:9

After 5 years the ratio of their ages will be = 4:5

Tσ fínd -

Their present Ages

Sσlutíσn -

Let the present ages of A and B be as -

➸ A = 7y

➸ B = 9y

$\rule{300}{1.5}$

Ages after 5 years be as -

➸ A = (7y + 5)

➸ B = (9y + 5)

$\rule{300}{1.5}$

According to the Question -

$\sf{\implies} \: \dfrac{(7y + 5)}{(9y + 5)} = \dfrac{4}{5}$

$\sf{\implies} \: Cross \: Multiply \:$

$\sf{\implies} \: 5(7y + 5) = 4(9y + 5)$

$\sf{\implies} \: 35y + 25 = 36y + 20$

$\sf{\implies} \: 36y - 35y = 25 - 20$

$\sf{\implies} \: y = 5$

$\rule{300}{1.5}$

$\textbf{Present age of A}$

$\sf{\implies} \: 7 \times 5$

$\sf{\implies} \: 35$

$\rule{300}{1.5}$

$\textbf{Present age of B}$

$\sf{\implies} \: 9 \times 5$

$\sf{\implies} \: 45$

$\therefore$ The present Ages of A and B are 35 and 45 respectively.