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When 39 is raised to the 100th power, the unit's digit of the answer will be?​

User Chane
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1 Answer

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The unit's digit of 39 raised to the 100th power is 9.

Explanation:

  • The unit digit of 39 is 9.
  • So, divide the power 100 by 9.

⇒ 100/9 = 11 and (remainder = 1)

Now check the unit digits of multiples of 9.


9^(1) = 9 ⇒ unit digit = 9


9^(2) = 81 ⇒ unit digit = 1


9^(3) = 729 ⇒ unit digit = 9


9^(4) = 6561 ⇒ unit digit = 1

  • The unit digit repeats as 9 for odd power and 1 for even power.
  • The remainder of 100/9 is 1, which is a odd number.
  • Therefore, the unit digit of
    39^(100) = 9
User Dshkol
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