How many different 3 digit numbers can you make?

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How many different 3 digit numbers can you make from the digits 1, 1 and 3? You can use each digit as many times as you like.

Comments

  1. Anonymous9 February 2021 at 08:36

    Well, for the first method, we can count the number of numbers that we can make:
    113
    131
    311

    For the second method, we can use combinatorics. As we know from other questions, if each number was different, then there would be 3! numbers or 6 numbers. Since, they are different then we need to do 6/2 = 3.

    As you can see, we got three for both answers.

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