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study
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 03:57
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(1001^2)-(999^2)/(101^2)-(99^2) =

10
20
30
50
100



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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 04:51
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Simple solution: use the property a^2-b^2 = (a+b) (a-b)
=
(1001+999)(1001-999) / (101+99)(101-99)
=
(2000)(2) / (200)(2)
=
10

ans. A
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subarao
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 08:22
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Another alternative way

(a+b)^2-(a-b)^2=4ab

so the above can be expressed as
(1000+1)^2-(1000-1)^2/(100+1)^2-(100-1)^2
=4*1000/4*100
=10
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 10:59
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subarao
Another alternative way

(a+b)^2-(a-b)^2=4ab

so the above can be expressed as
(1000+1)^2-(1000-1)^2/(100+1)^2-(100-1)^2
=4*1000/4*100
=10
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i also used the same method. answer is 10
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 13:04
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I have just begun looking at an MBA. I am assuming we cannot use calculators on the exam? Correct? Incorrect?
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subarao
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 24 Dec 2008, 22:08
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username309. Forget about calculator. You are not allowed even with your watch or a tissue paper.
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1001^2)-(999^2)/(101^2)-(99^2) = 10 20 30 50 100 28 Dec 2008, 07:14
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no need of calculator...GMAT checks basics



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This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
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