A. The greatest number of friends who can receive a necklace made from a combination of 72 blue and 42 red beads is 6.
B. Each friend will receive a necklace with 12 blue beads and 7 red beads.
The solution to this problem can be determined by considering the highest common factors of 72 and 42.
The common factors of 72 and 42 are 2 and 3.
The factors of 72 are 2, 3, and 12.
The factors of 42 are 2, 3, and 7.
2 x 3 = 6
When 6 divides 72 = 12
When 6 divides 42 = 7
Number of blue beads = 72
Number of red beads = 42
The highest number that can divide 72 and 42 without a remainder is 6.
Thus, each friend's necklace will contain 19 beads (12 blue beads and 7 red beads).
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