VeritasPrepKarishma wrote:

GMATPASSION wrote:

Lets say,

|a - c| = 4 . If c>a then we can surely say that c-a=4.

What about the inverse. If say we know that c-a=4 & c>a. How do we approach |a - c| = 4??

This may be a very simple question?? Pls help.

I am not sure I understand what you are asking but this is what I gathered:

If you know that c-a=4 & c>a, then you can say that |a - c| = 4.

If distance between c and a is 4 then distance between a and c is also 4. Keep in mind that mod represents distance. It doesn't matter where you measure it from.

Hi,

A visual representation on number line would be

----------a------c--------

----------c------a--------

The distance between a & c is 4 units.

Also, since mod is always positive, whenever one opens a modulus the value should come out as positive.

So, if c>a implies c-a>0

therefore, |a-c| or |c-a| = c-a

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