Answer:
LCM: 60
HCF: 10
Explanation:
Listing Multiples
LCM:
Multiples of 20:
20, 40, 60, 80, 100
Multiples of 30:
30, 60, 90, 120
Therefore,
LCM(20, 30) = 60
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Factorization
HCF:
The factors of 20 are: 1, 2, 4, 5, 10, 20
The factors of 30 are: 1, 2, 3, 5, 6, 10, 15, 30
Then the greatest common factor is 10