Exponents

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Exponents

by JimmyQ » Mon May 24, 2010 5:34 am
Question from MBA.com practice test:

The value of of 10^8 - 10^2 / 10^7 - 10^3 is closest to which of the following:

a) 1

b) 10

c) 10^2

d) 10^3

e) 10^4

Please explain how you solve this one :)

Thanks,

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by liferocks » Mon May 24, 2010 5:44 am
10^8 - 10^2 / 10^7 - 10^3
=1/10{(10^6-1)/(10^4-1)}

so numerator is slightly less than 10^6 and denominator is slightly less than 10^4

so the result will be around 10^6/10^4 or 10^2


IMO Ans [spoiler]10^2/10 or 10 i.e option B[/spoiler]

what is OA?
Last edited by liferocks on Mon May 24, 2010 8:05 am, edited 1 time in total.
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by krazy800 » Mon May 24, 2010 5:53 am
IMO B


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

(10^6) - 1 = 10^6 (approximately)

(10^4) - 1 = 10^4 (approximately)

simplifying we get

10^4/10^3 = 10

HTH
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by kstv » Mon May 24, 2010 5:54 am
JimmyQ wrote: The value of of 10^8 - 10^2 / 10^7 - 10^3 is closest to which of the following:
a) 1 b) 10 c) 10^2 d) 10^3 e) 10^4
10^8 - 10^2 / 10^7 - 10^3 =

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

10^x - 1 is very close to 10^x

10^6/10^(4+1) = 10

IMO B

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by liferocks » Mon May 24, 2010 8:04 am
oopss..I missed the 1/10completely.Thanks to krazy800 and kstv.corrected the previous post.
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