Question

please help.
2 years ago, age of brother was 3 times less than sister's age. this year his age is just 2 times less than his sister's. how old is brother? how old is sister?​

Answer 1

Answer:

$The\ brother's\ present\ age= 4\ years\\The\ sister's\ present\ age=8\ years$

Step-by-step explanation:

$Let\ the\ brother's\ present\ age\ be\ x\\Hence\ we\ are\ given,\\His\ sister's\ present\ age=(2x)\\Now,\\The\ brother's\ age\ before\ two\ years=(x-2)\\The\ sister's\ age\ before\ two\ years=3(x-2)\\Also,\\His\ sisters\ age\ before\ two\ years=2x-2\\Hence,\\3(x-2)=2x-2\\3x-6=2x-2\\3x-2x=6-2\\x=4\\Hence,\\The\ brother's\ present\ age= 4\ years\\The\ sister's\ present\ age=2x=2*4=8\ years$

Answer 2

Answer:

The sister's present age is 8 years old, and the brother's present age is 4 years old.

Step-by-step explanation:

Let $b =$ present age of the brother, $s =$ present age of the sister

$s-2 = (b-2)$ × $3$

$s-2$ = $3b - 6$

$s = 3b - 4$

$s = b$ × $2$

$= 2b$

$sb-4 = 2b$  (proved from above equations)

$b = 4$

$\because s = 3b - 4$

$\therefore$$s = 3$×$4 - 4$

$= 8$

$\therefore$ the brother's present age is 4 years old, and the sister's present age is 8 years old.

Hope this helps :)