Question

I'm 3 times younger than my mom but 3 times older than my younger brother. Mom is older than my younger brother by 40 years. how old am I?​

Answer 1

Given:

I'm 3 times younger than my mom but 3 times older than my younger brother.

Mom is older than my younger brother by 40 years.

To find:

How old am I.

Solution:

Let x be the age of the younger brother.

I'm 3 times older than my younger brother. So, my age is 3x.

I'm 3 times younger than my mom. So, she is 3 times older than me and her are is 3(3x)=9x.

The difference between the age mother and younger brother is 40 years.

`9x-x=40`

`8x=40`

Divide both sides by 8.

`x=(40)/(8)`

`x=5`

Now,

My age
`=3x`

`=3(5)`

`=15`

Therefore, I'm 15 years old.