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Question
Find the LCM and HCF of the following integers by applying the prime factorisation method.
12, 15 and 21
Solution
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12 = 2 × 2 × 3
15 = 3 × 5
21 = 3 × 7
H.C.F of 12, 15 and 21 = 3
L.CM of 12, 15 and 21 = 2 × 2 × 3 × 5 × 7
L.C.M of 12, 15 and 21 = 420
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