(1001^2 - 999^2)/(101^2 - 99^2)
1. 10
2. 20
3. 40
4. 80
5. 100
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beat_gmat_09
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Use formula - (a^2 - b^2) = (a+b)*(a-b)
(1001^2 - 999^2)/(101^2 - 99^2)
= (1001+999) * (1001-999) / (101+99)*(101-99)
= (2000 * 2) / (200 *2)
= 10
(1001^2 - 999^2)/(101^2 - 99^2)
= (1001+999) * (1001-999) / (101+99)*(101-99)
= (2000 * 2) / (200 *2)
= 10
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beat_gmat_09 wrote:Use formula - (a^2 - b^2) = (a+b)*(a-b)
(1001^2 - 999^2)/(101^2 - 99^2)
= (1001+999) * (1001-999) / (101+99)*(101-99)
= (2000 * 2) / (200 *2)
= 10
