1. The Highest Common Factor
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2. What are the factors of 45? 45 1 3 5 9 15 45
What are the factors of 36? 36 1 2 3 4 6 6 9 12 18 36
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3. What are the common factors of 45 and 36?1 3 5 9 15 45 36 1 2 3 4 6 6 9 12 18 36
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4. What is the highest common factor of 45 and 36?1 3 5 9 15 45
H.C.F. 36 1 2 3 4 6 6 9 12 18 36
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5. What are the factors of 28? 28 1 2 4 7 14 28
What are the factors of 42? 42 1 2 3 6 7 14 21 42
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6. What are the common factors of 28 and 42?1 2 4 7 14 28 42 1 2 3 6 7 14 21 42
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7. What is the highest common factor of 28 and 42?1 2 4 7 14 28 42 1 2 3 6 7 14 21 42
The H.C.F of 28 and 42 is 14
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8. What is the highest common factor of 24 and 54?1 2 3 4 6 8 12 24 54 1 2 3 6 9 18 27 54
The H.C.F of 24 and 54 is 6
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9. What is the highest common factor of 60 and 72?1 2 3 4 5 6 10 12 15 20 30 60 72 1 2 3 4 6 8 9 12 18 24 36 72
The H.C.F of 60 and 72 is 12
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10. Class-work Find the Highest Common Factor of these sets of numbers:
6 and 9
8 and 12
12 and 15
12 and 20
12 and 18
20 and 24
18 and 24
18 and 30
18 and 36
20 and 32
28 and 42
20 and 64
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11. © T Madas