1.   Look at the factors of 18 and 30. What is the greatest common factor?
factors of 18: 1, 2, 3, 6, 9, 18
factors of 30: 1, 2, 3, 5, 6, 10, 15, 30
    A. 6 B. 5
    C. 3 D. 2
    Hint

  2.   Find the GCF of 24 and 54.
    A. 2 B. 3
    C. 6 D. 12
    Hint

  3.   Find the GCF of 16, 12, and 36.
    A. 3 B. 2
    C. 4 D. 6
    Hint

  4.   Find the GCF of 38 and 49.
    A. 1 B. 4
    C. 3 D. 2
    Hint

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