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GMATBLACKBELT
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Calculate 999*999 in your head... GO 30 Apr 2008, 08:56
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Calculate 999*999 in your head... GO!



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FN
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Calculate 999*999 in your head... GO 30 Apr 2008, 09:06
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my method by far isnt the best..

(1000-1)(1000-1)=1000*1000-2000+1
1000,000
2,000
998,000
1
998,001
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bkk145
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Calculate 999*999 in your head... GO 30 Apr 2008, 09:47
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GMATBLACKBELT
Calculate 999*999 in your head... GO!
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(1000-1)*999 = 999000 - 999 = 999000 - (1000 - 1)
= 998000+1 = 998001
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GMATBLACKBELT
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Calculate 999*999 in your head... GO 30 Apr 2008, 10:15
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Good job. Thats how I did it as well.

This was on the analyst forum. Apparently it was an interview question... yikes!
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rpmodi
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Calculate 999*999 in your head... GO 30 Apr 2008, 14:56
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GMATBLACKBELT
Good job. Thats how I did it as well.

This was on the analyst forum. Apparently it was an interview question... yikes!
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I can apply vedic math rule here :-)

999*999

999 - -1
999 - -1

subtract (999-1) first part of our solution 998 second part multiply last column gives us 001

so the answer 998001 :-)

same way 996*995 ?

996 -4
995 -5

991020

Now can you guys do 57*58 in your head ?



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Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
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Thank you for understanding, and happy exploring!