# Two-digit numbers are formed, with replacement, form the digits 0 through 9. How many two-digit even numbers are possible?

Question
Discrete math
Two-digit numbers are formed, with replacement, form the digits 0 through 9.
How many two-digit even numbers are possible?

2020-12-02
There are 9 choices for the first digit since 9 cannot be the first digit. There are 5 choices for the second digit because even numbers end in 0, 2, 4, 6, or 8. By Fundamental Counting Principle, there are 9 = 45 possible two-digit even numbers.
45

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