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2019 AMC 10A Problem 20

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2019 AMC 10A Problem 20AMC 10 Step by Step
Name:                             Date: September 13, 2026
Basic Probability · difficulty 4 of 5 · about 5 min · position P16-20

The numbers 1,2,…,91,2,\dots,9 are randomly placed into the 99 squares of a 3×33 \times 3 grid. Each square gets one number, and each of the numbers is used once. What is the probability that the sum of the numbers in each row and each column is odd?

  1. A)

    121\dfrac{1}{21}

  2. B)

    114\dfrac{1}{14}

  3. C)

    563\dfrac{5}{63}

  4. D)

    221\dfrac{2}{21}

  5. E)

    17\dfrac{1}{7}

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