GMAT Prep

hi rookieingmat.

The answer should be B.

10^8-10^2
------------ =
10^7-10^3


10^2(10^6 - 1)
----------------- =~
10^3(10^4 - 1)

10^6
----- ~ 10
10^4 * 10

Thats the correct answer. Thanks, PandeyVineet24!

Could you please elobrate on how you do this
10^2(10^6 - 1)
----------------- =~
10^3(10^4 - 1)

10^6
----- ~ 10
10^4 * 10

rookieingmat wrote:could someone solve this?

The value of

10^8-10^2
------------
10^7-10^3

A. 1
B. 10
C. 10^2
D. 10^3
E. 10^4

This problem has been discussed before - it's always good to search the forums before posting!

There's a much simpler way to solve this question, and that's through estimation.

Let's look at the top:

10^8 - 10^2

Well, 10^2 is pretty insignificant compared to 10^8 (100 is a LOT smaller than 100000000). So, we can estimate the numerator as simply 10^8.

Same thing on the bottom:

10^7 - 10^3

10000000 is a LOT more than 1000. We can estimate the denominator as simply 10^7.

So, we really have:

10^8/10^7 = 10^1 = 10

ok I got it now, Basically 10^6-1 and 10^4-1 are approximately 10^6 and 10^4.
Thanks Stuart.

I was under the impression that 10^8-10^2 = 10^6/
10^7-10^3 = 10^4
which would equal 10^2
why doesn't this work whoud the question does state closest to the following

rookieingmat wrote:could someone solve this?

The value of

10^8-10^2
------------
10^7-10^3

A. 1
B. 10
C. 10^2
D. 10^3
E. 10^4

None of them is the correct answer because the way you asked this question is looking for a VALUE. If you had asked "approximately", answer should have been 10 otherwise it is actually:

F) 10.0009901