How do you find the Least common multiple of ##28, 14, 21##?

84
##color(red)(“A very different approach“)##
##ul(“number “|larr”prime factors “rarr|)##
##ul(” 14: 2 7 “)##
##ul(” 21: 3 7 “)##
##ul(” 28: 2 2 7 “)##
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The maximum occurrence of 2 on the lines is two times
So the beginnings of our LCM is ##” “2xx2##
…………………………………………………………………………….
The maximum occurrence of 3 on the lines is 1 times
So the next stage of LCM is ##” “2xx2xx3##
……………………………………………………………………………………….
The maximum occurrence of 7 on the lines is 1 times
So the last stage of LCM is ##” “2xx2xx3xx7 = 84##