PS Exponents Question

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PS Exponents Question

by dnkcdnguy » Sat Jan 17, 2009 1:53 pm
Hi All,

I seem to have difficulty doing these types of questions quickly. Can someone please let me know how to solve the below question and if possible, a quick method.

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

A) 1
B) 10
C) 10^2
D) 10^4
E) 10^5

A: 10

Thanks
"If you fail to plan,..then you plan to fail"
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by sonu_thekool » Sat Jan 17, 2009 3:28 pm
You can try to extract common elements out. Here try taking 10^2 out.

10^2(10^6 - 1) / 10^2(10^5 - 10)
= (10^6 - 1) / (10^5 - 10)
which is approximately equal to 10^6 / 10^5 = 10

Hope this helps.

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by dnkcdnguy » Sat Jan 17, 2009 4:41 pm
That helps a lot!

Now I know the quicker route. I have to remember to factor first :)

Thanks
"If you fail to plan,..then you plan to fail"