Answer:
Step-by-step explanation:
Problems like these are aided immensely by your knowledge of multiplication tables.
1) 36 = 1·36 = 2·18 = 3·12 = 4·9 = 6·6
27 = 1·27 = 3·9
The greatest common factor is 9, so the sum can be written as 9(4+3).
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2) 45 = 1·45 = 3·15 = 5·9
25 = 1·25 = 5·5
The greatest common factor is 5, so the sum can be written as 5(9+5).
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3) 16 = 1·16 = 2·8 = 4·4
72 = 1·72 = 2·36 = 3·24 = 4·18 = 6·12 = 8·9
The greatest common factor is 8, so the sum can be written as 8(2+9).
