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by hariharakarthi » Mon Aug 31, 2009 7:26 pm
Ans 1.

(7^(12x+3)+3) MOD 5
((7^12x)(7^3))MOD 5 + 3 MOD 5

Taking only the underlined part,
((7^12x)MOD 5 )(7^3 MOD 5)
((2^12x)MOD 5)(2^3 MOD 5)
((2^4)^3x) MOD 5 * (8 MOD 5)
((16)^3x MOD 5)* 3
((1)^3x MOD 5)*3
1*3 = 3
1^n =1. 1 power of anything equal to 1.

Now, including the second part also,
3+3 = 6 MOD 5 = 1.
Hence ans is 1.
OA please.
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by mlaboda » Tue Sep 01, 2009 5:08 am
OA is 1. Thanks for the explanation!!
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by GMATandCFA » Tue Sep 01, 2009 4:26 pm
Whaat is MOD?
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by mlaboda » Sun Sep 06, 2009 8:42 am
I've got another problem for you, hariharakarthi. As you will see, it's similar to this problem, and two other people have posted answers. However, the two people disagree on the correct answer, so I'd like to see what you get. Thx for your help!!

https://www.beatthegmat.com/viewtopic.ph ... 969#187969
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