Question

Silpa’s father is 25 years older than Silpa. After 10 years, he will be twice as old as Silpa. Find their present ages?

Answer 1

$QUESTION:$

Silpa’s father is 25 years older than Silpa. After 10 years, he will be twice as old as Silpa. Find their present ages ?

$SOLUTION:$

Let Silpa's age be x years.

So her father's age = (x + 25) years.

After 10 years,

• Silpa's age = (x+10) years.
• His father age = ( x + 25 + 10 ) = ( x + 35) years.

According to question,

(x+10)2 = ( x + 35)

⇒  2x + 20 = x+35

∴ x = 35 - 20 = 15.

Their present age :

• Silpa = x = 15 years.
• Her father = x + 25 = 15 + 25 = 40 years.

Thanks..

Answer 2

Let Silpa Age= X years
Then her father age=(X+25) years

After 10 years
Silpa Age=(X+10) years
Her Father age=(X+25+10) years

Now He will be twice.
Equation
2(X+10)=X+25+10

Now You wonder why we Multiply 2 to age of Silpa because we using linear equation in which LHS=RHS
So,if we Multiply 2 to age of Silpa it will equal age of her father.

2(x+10)=x+25+10
2x+20=x+35
2x-x=35-20
x=15

Silpa Age=15 years
Father Age=15+25=40 years