Half of me!!

Level pending

When I was 2 years old, my sis was half of my age. Now I am 18 years old, what is the age of my sis?

The answer is 17.

3 solutions

Eduardo Petry
Dec 31, 2013

Your sis age when you were two $\displaystyle=\dfrac{2}{2}=1$ . The difference of ages is $\displaystyle2-1=1$ .

If you are $\displaystyle18$ , your sis is $\displaystyle18-1=\boxed{17}$

but it's must be half of it

Shubham Chaudhary - 7 years, 5 months ago

why is it happen that the ans. is 17 in this problem?
I think in law of proportion in math the solution must like this

formula:

a/b=c/d or a:b=c:d

sol'n

2/1=18/Y then cross multiply

2xY=18x1 then simplify

2Y=18

Y=18/2

Y=9

Karren Barrameda - 7 years, 5 months ago

Vasavi's sis was half her age only when Vasavi was $\displaystyle2$ years old. So the difference of ages is of $\displaystyle1$ year. It's not really proportional, you see?

Eduardo Petry - 7 years, 5 months ago

Prasun Biswas
Feb 13, 2014

When she was $2$ years old, her sister was half of her age, i.e, $\frac{2}{2}=1$ years old.

After $16$ years. she becomes $18$ years old, so her sister's age should be $=(1+16)=\boxed{17 \text{ years old }}$

Sanghamitra Anand
Feb 12, 2014

Half of 2 is 1. So, her sister was 1 year old and 1 year younger than her. Therefore, when she is 18 years old, her sister must be 17!

Half of me!!

The answer is 17.

3 solutions

0 pending reports