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2016 AMC 10A Problem 9

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2016 AMC 10A Problem 9AMC 10 Step by Step
Name:                             Date: September 13, 2026
Sequences & Series · difficulty 2 of 5 · about 2 min · position P1-10

A triangular array of 20162016 coins has 11 coin in the first row, 22 coins in the second row, 33 coins in the third row, and so on up to NN coins in the NN th row. What is the sum of the digits of NN ?

  1. A)

    66

  2. B)

    77

  3. C)

    88

  4. D)

    99

  5. E)

    1010

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