How many different three-digit numbers can be formed using the digits 1,3,5,7 and 9 if the digits may be repeated?
What is 5x5x5 ?
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To find the number of different three-digit numbers that can be formed using the digits 1, 3, 5, 7, and 9 with repetition allowed, we can use the concept of permutations.
Since repetition is allowed, there are five choices for each digit (1, 3, 5, 7, or 9) for each position (hundreds, tens, ones). Therefore, there are 5 choices for the hundreds digit, 5 choices for the tens digit, and 5 choices for the ones digit.
To determine the total number of different three-digit numbers, we multiply the number of choices for each digit:
Number of different three-digit numbers = (Number of choices for hundreds digit) × (Number of choices for tens digit) × (Number of choices for ones digit)
Number of different three-digit numbers = 5 × 5 × 5
Number of different three-digit numbers = 125
Therefore, there are 125 different three-digit numbers that can be formed using the digits 1, 3, 5, 7, and 9 with repetition allowed.