To find the common factors of the numbers 15, 45, and 90, we first need to determine the factors of each individual number.
Factors of 15: The factors of 15 are 1, 3, 5, and 15.
Factors of 45: The factors of 45 are 1, 3, 5, 9, 15, and 45.
Factors of 90: The factors of 90 are 1, 2, 3, 5, 6, 9, 10, 15, 18, 30, 45, and 90.
Next, we identify the factors that are common to all three numbers. By looking at the factors listed above, the common factors are:
- 1
- 3
- 5
- 15
Therefore, the common factors of 15, 45, and 90 are 1, 3, 5, and 15.