Andy C. answered • 09/09/17

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4 digit numbers:

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ends with zero, there are 4 choices for the first digit, 3 choices for the 2nd digit, and 2 choices for the 3rd digit.

4x3x2 = 24

ends with 2: there are only 3 choices for the first digit because the first digit cannot be zero, as that

would make it 3 digit number. there are 3 choices for the 2nd digit, and 2 choices for the 3rd digit.

3 x 3 x 2 = 18.

So there are 24 + 18 = 42 ways to create an 4 digit even integer.

5 digit number:

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ending with zero: there are 4 choices for the first digit, 3 choices for the 2nd digit, 2 choices for the 3rd digit, and

one digit remaining for the 4th digit. 4x3x2x1 = 24.

ending with 2: There are only 3 choices for the 1st digit because zero in the first digit makes it a 4 digit number.

There are 3 choices for the 2nd digit, 2 choices for the 3rd digit, and one digit remaining for

the 4th digit. 3 x 3 x 2 x1 = 18.

Again there are 24 + 18 = 42 ways to create an even 5 digit integer.

42 + 42 = 84

Abdul A.

09/09/17