The proper factors of a number are all the factors of the number with the exception of the number itself. For example, the factors of 12 are 1, 2, 3, 4, 6, and 12. After removing 12, the proper factors of 12 are 1, 2, 3, 4, and 6.
1.
What are the proper factors of 10?
The factors of 10 are 1, 2, 5, and 10. The proper factors of 10 are 1, 2, and 5.
2.
What are the proper factors of 15?
The factors of 15 are 1, 3, 5, and 15. The proper factors of 15 are 1, 3, and 5.
3.
What are the proper factors of 7?
The factors of 7 are 1 and 7. The only proper factor of 7 is 1.