Question

Two number are in ratio 3:7. If 4 is added to each of them, then the ratio becomes 1:2. Find the number
​

Answer 1

Answer:

LOOK CAREFULLY

Step-by-step explanation:

LET THE COMMON FACTOR BE X

HENCE

or,(3x+4)/(7x+4)=1/2

By,cross multiplication ;

or,2(3x+4)= 1(7x+4)

or,6x + 8 = 7x + 4

or, 6x - 7x = 4-8

or, - x = - 4

or, x=4

Hence, one number = 3x = 3(4) = 12

Another number = 7x = 7(4) = 28

Answer. The two numbers are 12 and 28.

Answer 2

Given:-

• Two numbers are in the ratio 3 : 7
• If 4 is added to each of them, then the ratio becomes 1 : 2

Solution:-

Two numbers are in the ratio 3 : 7

Let the actual ratio be 3x : 7x

If 4 is added to each of them, then the ratio becomes 1 : 2

i.e. (3x + 4) : (7x + 4) = 1 : 2

$\sf{\dfrac{(3x+4)}{(7x+4)} = \dfrac{1}{2}}$

$\sf{2(3x+4) = 7x+4}$

$\sf{6x + 8 = 7x+4}$

$\sf{6x-7x = 4 - 8}$

$\sf{-x = -4}$

$\sf{x = 4}$

Therefore, the numbers are

3x = 3(4) = 12

7x = 7(4) = 28