Vasudha wrote:Dear friends,

Here is a powerprep question that I am not able to understand.

If y>= 0, what is the value of x?

1. |x-3| >= y
2. |x-3| <= -y


The software says statement (2) alone is sufficient but I dont understand why..

Thanks for your help!

ok basics first modulus x is always positive....

according to the first statement... we have mod ( x-3) >= y... so the only thing that we get from this statement is that y is also positive... so not sufficient...

according to the second statement... mod (x-3)<=-y.... now y cant be greater than 0 bcoz then mod (x-3) will have to be negative....which is not possible... therefore y=0.... therefore x will have to be equal to 3... which will make mod(x-3)=0...... hence statement 2 alone is sufficient

the only thing to remember is that a mod is always positive....

Thanks a lot Gabriel. Now I understand it.

Hey Gabriel really simplified explanation!

Cheers!