Q:

How many 5-digit (positive) even numbers can be formed using the digits 4, 6, 7, 2, 8 if digits can be repeated?

Accepted Solution

A:
In this problem, since the digits can be repeated, you have to know how many possible digit can be used in every digit of a five – digit number. On the first digit of the number, there are 5 possible digits. The second digit of the number has 5 possible digits as well. The third digit of the number has 5 possible digits. The fourth and the fifth digit will have 5 possible digits as well. Multiplying the possible digits for each digit of a five – digit number: 5 x 5 x 5 x 5 x 5 = 3,125 possible five – digit numbers