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Question
Find the LCM and HCF of the following integers by applying the prime factorisation method:
84, 90 and 120
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Solution
84, 90 and 120
Let us first find the factors of 84, 90 and 120
`84=2^2xx3xx7`
`90=2xx3^2xx5`
`120=2^3xx3xx5`
L.C.M of 84,90 and 120 =`2^3xx3^2xx5xx7`
L.C.M of 84,90 and 120 = 2520
H.C.F of 84,90 and 120 =6
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