To find all possible two-digit numbers that can be formed using the digits 3, 7, and 9 with repetition allowed, we follow a simple combinatorial approach.
For two-digit numbers, the first digit (tens place) can be any of the three digits: 3, 7, or 9. The second digit (units place) can also be any of the three digits, since repetition is allowed.
This means:
- First digit choices: 3 options (3, 7, 9)
- Second digit choices: 3 options (3, 7, 9)
Now, to calculate the total number of combinations, we multiply the number of choices for the first digit by the number of choices for the second digit:
Total combinations = 3 (first digit) × 3 (second digit) = 9
Here are the two-digit numbers that can be formed:
- 33
- 37
- 39
- 73
- 77
- 79
- 93
- 97
- 99
In conclusion, the possible two-digit numbers formed by using the digits 3, 7, and 9 with repetition allowed are: 33, 37, 39, 73, 77, 79, 93, 97, and 99.