1.   Find the GCF of 28 and 34.
    A. 1 B. 4
    C. 2 D. 7
    Hint

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

  3.   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. 8 B. 16
    C. 4 D. 2
    Hint

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

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