What is the units digit of the solution to 177^28 - 133^23?
PS NOT: ^ signifies raised to the power
(A) 1
(B) 3
(C) 4
(D) 6
(E) 9
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singh_amit19
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the 28th exponent of 7 will have the units digit as 1.
The 23rd exponent of 3 will have units digit as 7.
Therefore (1-7) = 4
Answer is C
The 23rd exponent of 3 will have units digit as 7.
Therefore (1-7) = 4
Answer is C
