Question

The ages of A and B are in the ratlo 3: 4. If the ratio of their ages 15 years back was 3: 5, find the sum of their
present ages.​

Answer 1

Answer:

The present ages of A and B are 30 and 40 years respectively.

The sum of their present ages is 70.

Step-by-step explanation:

Given :

Ratio of A and B's ages = 3 : 4

Ratio of their ages 15 years ago = 3 : 5

To find :

Their present ages

Solution :

Let their present ages be -

• A as 3x
• B as 4x

Ages 15 years ago -

• A = (3x - 15)
• B = (4x - 15)

★ $\boxed{\sf{ \frac{3x - 15}{4x - 15} = \frac{3}{5}}}$

$\sf{\longrightarrow} \: {\dfrac{3x - 15}{4x - 15} = \dfrac{3}{5}} \\ \\ \sf{\longrightarrow} \:5(3x - 15) = 3(4x - 15) \\ \\ \sf{\longrightarrow} \:15x - 75 = 12x - 45 \\ \\ \sf{\longrightarrow} \:15x - 12x = - 45 + 75 \\ \\ \sf{\longrightarrow} \:3x = 30 \\ \\ \sf{\longrightarrow} \:x = \dfrac{30}{3} \\ \\ \sf{\longrightarrow} \:x = 10$

$\rule{300}{1.5}$

★ Value of 3x

$\sf{\longrightarrow} \:3(10) \\ \\ \sf{\longrightarrow} \:30$

A is 30 years old

$\rule{300}{1.5}$

★ Value of 4x

$\sf{\longrightarrow} \:4(10) \\ \\ \sf{\longrightarrow} \:40$

B is 40 years old

The present ages of A and B are 30 and 40 years respectively.

$\rule{300}{1.5}$

Sum of their present ages =

$\longrightarrow$ 30 + 40

$\longrightarrow$ 70

$\therefore$ The sum of their present ages is 70.

Answer 2

Answer...

Let the ages of A and B is 3x and 4x respectively....

Let the ages of A and B is 3x and 4x respectively....So, 15 years back

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ,

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15)

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30 » X= 10 years

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30 » X= 10 yearsSo, the age of age is 3X = 3×10 = 30 years.

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30 » X= 10 yearsSo, the age of age is 3X = 3×10 = 30 years.The age of B is 4X = 4×10 = 40 years..

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30 » X= 10 yearsSo, the age of age is 3X = 3×10 = 30 years.The age of B is 4X = 4×10 = 40 years..Hope this will help you...

Let the ages of A and B is 3x and 4x respectively....So, 15 years back Their ages was 3x-15 and 4x -15 respectively...ATQ, »3x-15/4x-15= 3/5 »5(3x-15)= 3(4x-15) »15x- 45= 12x - 15 » 15x-12x= -15+ 45=30 »3x = 30 » X= 10 yearsSo, the age of age is 3X = 3×10 = 30 years.The age of B is 4X = 4×10 = 40 years..Hope this will help you...Mark as brainliest ☺️

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