1.   Based on the factor trees, what is the greatest common factor of 8 and 20?
    A. 20 B. 8
    C. 4 D. 2

  2.   What is the greatest common factor of 16x2 and 12x?
    A. 4x2 B. 16x2
    C. 12x D. 4x

  3.   George wants to resurface the table below with ceramic tiles. What is the largest square tile that he can use without having to cut any tiles?
    A. 6 inches on each side B. 8 inches on each side
    C. 12 inches on each side D. 4 inches on each side

  4.   What is the greatest common factor of 20x2 and 32x3?
    A. 4x B. 4x2
    C. 8x D. 8x3

  5.   Janice has three pieces of string that are 36 cm, 24 cm, and 18 cm in length. She needs to have strings that are all the same length, but she does not want to waste any string. What is the greatest length Janice can cut each piece of string into and still have equal lengths?
    A. 6 cm B. 12 cm
    C. 3 cm D. 9 cm

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