Question

Shalini is younger than Rohini by 7 years. If their ages are in the respective ratio of 7:9, how old is Shalini?​

Answer 1

Given :

• Shalini is younger than Rohini by 7 years. If their ages are in the respective ratio of 7:9

To Find :

• how old is Shalini?

Solution :

Let Rohini age be x years.

Then, Shalini's age

= (x - 7) years.

(x - 7)/x = 7/9

9x - 63 = 7x

2x = 63

x = 31.5

Hence, Shalini age

= (x - 7)

= 24.5 years.

Hence , shalini age is 24.5 years

Answer 2

To Find:-

Age of Shalini .... ( ? )

Given:-

Ages of Shalini and Rohini in ratio =7:9 respectively

Solution:-

step-by-step explanation:

Let Rohini's age be ( x ) years

Let Shalini's age be ( x - 7 ) years

Ratio of ages = 7 : 9

Now,

By the problem,

To get Shalini's age we need to find Rohini's age first

$\implies \dfrac{x - 7}{x} = \dfrac{7}{9}$

$\implies9x - 63 = 7x$

$\implies \: 9x - 7x = 63 \: \: \: \\ {(by \: \: transposing \: 7x \: to \:L.H.S \: and \: \:transposing \: 63 \: \: to \: R.H.S)}$

$\implies2x = 63$

$\implies \dfrac{63}{2} \\ \implies31.5$

$So, Age \: of \: Rohini \: is \: \: 31\frac{1}{2} \: years \: old.$

Now , Shalini's age :-

$\implies( 31 \dfrac{1}{2} - 7) \: years \\ \implies 24\dfrac{1}{2} \: years$

Answer:-

$\therefore \: Age \: of \: Rohini \: \: is \: 31\dfrac{1}{2} \: years$

$Age\: \: of\: \:Shalini\: \:is \: 24\dfrac{1}{2} years$