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Re: What is the units digit of (1337)^124(13)^27(9)^5?
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04 Jul 2023, 10:13
To determine the unit's digit of the given expression, we can focus on the unit's digit of each individual term and then find the unit's digit of their product.
Let's analyze the unit's digits of each term:
(1337)^124: The unit's digit of 1337 is 7. Since the unit's digit of 7 raised to any positive power follows a pattern of 7, 9, 3, 1, repeating, the unit's digit of (1337)^124 will be 1.
(13)^27: The unit's digit of 13 is 3. When 3 is raised to any positive power, the unit's digit follows a pattern of 3, 9, 7, 1, repeating. Therefore, the unit's digit of (13)^27 will be 7.
(9)^5: The unit's digit of 9 raised to any positive power is always 9.
Now, let's find the unit's digit of their product:
Unit's digit of (1337)^124(13)^27(9)^5 = (1)(7)(9) = 63.
Therefore, the unit's digit of the expression (1337)^124(13)^27(9)^5 is 3.
Answer: B