zerotoinfinite2006 wrote:

Find the unit's digit in the product (2467)^153 * (341)^72

(A) 0

(B) 1

(C) 2

(D) 7

(E) 9

7^x = 7 9 3 1 (repeats)

Where x starts from 1

Hence, units digit of 7^10 = units digit of 7^150 = 9

& units digit of 7^153 = 7

1^72 = 1

Hence ans = 7

It will be good to memorize the foll for exam day:

\(2^x\) = 2 4 8 6

\(3^x\)= 3 9 7 1

\(4^x\) = 4 6

\(5^x\) = 5

\(6^x\) = 6

\(7^x\) = 7 9 3 1

\(8^x\) = 8 4 2 6

\(9^x\) = 9 1

\(10^x\) = 0

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If you analyze enough data, you can predict the future.....its calculating probability, nothing more!