1.   Which two numbers have a GCF of 9?
    A. 36, 45 B. 45, 95
    C. 18, 36 D. 36, 39
    Hint

  2.   Look at the factors of 24 and 16. What is the greatest common factor?
factors of 16: 1, 2, 4, 8, 16
factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
    A. 16 B. 2
    C. 4 D. 8
    Hint

  3.   Find the GCF of 32 and 42.
    A. 2 B. 3
    C. 4 D. 14
    Hint

  4.   Find the GCF of 33, 48, and 54.
    A. 8 B. 1
    C. 3 D. 2
    Hint

  5.   Which two numbers have a GCF of 7?
    A. 35, 126 B. 25, 45
    C. 7, 17 D. 21, 63
    Hint