Question

10 years ago, sitas mother was 4 times older than her daughter. After 10 years, the mother will be twice older than the daughter. What is the present age of sits?

Answer 1

Let the present age of sita =x years
Let the present age of sita's mother= y years

According to the question-
10 years ago-
(y-10)=4(x-10)
=>y-10=4x-40=>40-10=4x-y
=>4x-y=30
=>x=(30+y)/4 ••••••••(1)

After 10 years-
(y+10)=2(x+10)
=>y+10=2x+20
=>y-2x=10
Putting the value of 'x' from equation(1), we get-
y-2(30+y)/4=10
=>y-(30+y)/2=10
=>2y-30-y=20. (Take LCM)
=>y-30=20
=>y=50

Putting the value of 'y' in equation(1), we get-
x=(30+50)/4=80/4=20

Hence, sita's present age is 20 years.