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2018 AMC 10A Problem 7

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2018 AMC 10A Problem 7AMC 10 Step by Step
Name:                             Date: September 13, 2026
Exponents, Logarithms & Radicals · difficulty 2 of 5 · about 3 min · position P1-10

For how many (not necessarily positive) integer values of nn is the value of 4000⋅(25)n4000\cdot \left(\tfrac{2}{5}\right)^n an integer?

  1. A)

    33

  2. B)

    44

  3. C)

    66

  4. D)

    88

  5. E)

    99

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