Question

Present age of Sanchi and her sister Trishika is in the ratio 11 : 18. four years ago ,Trishika was twice her sister's age. Find the age of both the sisters. ​

Answer 1

Answer:

Age of Sanchi = 11 , age of Trishika = 18.

Step-by-step explanation:

Let the present age of Sanchi be 11a year Trishika be 18a year.

Four year ago :

= > Age of Sanchi = Present age - 4 year

= > Age of Sanchi = ( 11a - 4 ) year

= > Age of Trishika = present age - 4 year

= > Age of Trishika = ( 18a - 4 ) year

According to the question : Four years ago ,Trishika was twice her sister's age.

= > Age of Trishika = 2 x age of Sanchi

= > ( 18a - 4 ) year = 2( 11a - 4 ) year

= > 18a - 4 = 22a - 8

= > 8 - 4 = 22a - 18a

= > 4 = 4a

= > 1 = 4

Hence,present age of Sanchi is 11a year = 11( 1 ) year = 11 year

Present age of Trishika is 18( 1 ) year = 18 year

Answer 2

Question :

The present age of Sanchi and her sister Trishika is in the ratio 11 : 18. Four years ago, Trishika was twice her sister's age. Find the age of both the sisters.

Solution :

$\underline{\bold{Given:}}$

• The present age of Sanchi and her sister Trishika is in the ratio = 11:18
• Four years ago, Trishika was twice Sanchi's age.

$\underline{\bold{To\:Find:}}$

• The present age of Sanchi and Trishika.

Let the present age of Sanchi and Trishika be 11x years and 18x years.

Four years ago :

• The age of Sanchi = (11x-4) years
• The age of Trishika = (18x-4) years

It is given that four years ago, Trishika was twice Sanchi's age.

$\therefore{18x-4=2(11x-4)}$

$\implies 18x - 4 = 2(11x - 4) \\\implies 18x - 4 = 22x - 8 \\ \implies - 4 + 8 = 22x - 18x \\ \implies 4 = 4x \\ \implies \frac{4}{4} = x \\ \implies 1 = x\\ \implies x = 1$

$\boxed {\green{\therefore {The\:present\:age\:of\:Sanchi\: is\: (11\times 1)\:years=11\:years.}}}$

$\boxed {\green{\therefore {The\:present\:age\:of\:Trishika\: is\: (18\times 1)\:years=18\:years.}}}$