Question

find LCM and HCF of12, 15,21 applying prime factorization method​

Answer 1

12=2*2*3

15=3*5

21=3*7

LCM=3*7*5*2*2=420

HCF=3

Answer 2

22,31,51 and 71 are the greatest powers involved in the prime factors of 12,15 and 21. so,LCM (12,15,21) =22X31X51X71=420