Question

Sonu is five times as old as her friend priya. After five years, Sonu will be thrice as old as Priya. Find their ages are

Answer 1

Answer:

Sonu is 25 years old and Priya is 5 years old.

Step-by-step explanation:

Let the age of Sonu be $x$ and the age of Priya be $y$.

Given that  Sonu's age is five times the age of her friend Priya. We can write it as,

$\implies x=5\times y=5y\hspace {2cm}(1)$

After five years Sonu's age will be three times the age of Priya. After 5 years their ages will be $x+5$ and $y+5$. So we have,

$x+5=3(y+5)$

Expand and simplify to obtain,

$\implies x+5=3y+15\\\\\implies x=3y+15-5=3y+10\\\\\implies x= 3y+10\hspace {3cm}(2)$

Solve the above two equations (1) and (2), we obtain

$\implies 5y-3y-10=0\\\\\implies 2y=10\\\\\implies y=5$

So the age of Priya is 5 years and the age of Sonu is 25 years.