shortcuts in finding the last two digits
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- vigneshraj
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When an integer with an ODD UNITS DIGIT OTHER THAN 5 is raised to A POWER THAT IS A MULTIPLE OF 20, the last two digits of the result are 01.vigneshraj wrote:(1941^3843)+(1961^4181)
Thus, the last two digits of 1941³��� and 1961�¹�� are 01.
To determine the last two digits of 1941³��³ and 1961�¹�¹, keep multiplying the last two digits by 41.
Last two digits of 1941³��³:
1941³��� --> 01.
1941³��¹ --> 01*41 = 41.
1941³��² --> 41*41 = 1681.
1941³��³ --> 81*41 = 3321.
Thus, the last two digits of 1941³��³ are 21.
Last two digits of 1961�¹�¹:
1961�¹�� --> 01.
1961�¹�¹ --> 01*61 = 61.
Thus, the last two digits of 1961�¹�¹ are 61.
Thus:
(last two digits of 1941³��³) + (last two digits of 1961�¹�¹) = 21+61 = 82.
Interesting question, but beyond the scope of the GMAT.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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