jainrahul1985 wrote:K = 35000/(250-2.5c)
where 100000 < K < 300000
Find value of c ?
1)19 2)29 3)39 4)49 e)59
Let's start by simplifying the question to:
k = 35000/x
where 100000<k<300000
For this to be true, x must be a fraction (dividing by a fraction increases the value of the right side).
For example, if x = 1/5, then k=5*35000 = 175000
Solving for the two boundaries:
100000 = 35000/x
x = 35000/100000 = 35/100 = 7/20
300000 = 35000/x
x = 35000/300000 = 35/300 = 7/60
So:
7/60 < x < 7/20
Subbing back in:
7/60 < 250-2.5c < 7/20
Multiplying by 60:
7 < 15000 - 150c < 21
-14993 < -150c < -14979
14993 > 150c > 14979
14993/150 > c > 14979/150
Well, 15000/150 = 100, so c is going to be a bit less than 100. Fortunately, no answer choice matches.
I say "fortunately", because this is a patently ridiculous question that required way too much calculation to answer - you'll never see anything that crazy on the GMAT. The algebra is challenging, if you like that kind of thing (and hey, I'm an algebra geek, which is why I solved it), but certainly not something you'll need to do on Test Day.
What's the source?
