Answer:
Part A: 60
5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60.
12, 24, 36, 48, 60.
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Part B: 9
81 / 72 = 9
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Part C: 9 (8 + 9)
GCF of 72 and 81 is 9...
Divide 72 by 9 and get 8.
Divide 81 by 9 and get 9.
To check multiply 9 with 8, and multiply 9 by 9.
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Easy! :D (if you don't mind, may I get brainliest please?)