prep #22

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prep #22

by dunkin77 » Tue Apr 24, 2007 2:00 pm
Hi,

I thought the answer should be 10^2 but turned out to be 10 -- Can you please show me??
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by jayhawk2001 » Tue Apr 24, 2007 9:17 pm
Compared to 10^8, 10^2 is a very small number. So, the difference
is approx 10^8

Similarly 10^7-10^3 is approx 10^7

So, the fraction boils down to 10^8/10^7 = 10

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by Cybermusings » Wed Apr 25, 2007 4:58 am
(10^8 - 10^2) / (10^7 - 10^3)

Take 10^2 common in the numerator
10^2 [ 10^6 - 1]
Take 10^2 common in the denominator also
10^2 [10^5 - 10]

So it becomes 10^2 [ 10^6 - 1] / 10^2 [10^5 - 10]
or 10^6 - 1 / 10^5 - 10
or 1000000-1 / 100000 - 10
or 999999/99990
Approximately 10

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