What is LCM of 20 and 24

Question

I want (LCM) of 20 and 24 the Lowest common Multiple so plz tell me the (LCM) of 20 and 24

Answer 1

LCM of 20 and 24

write the prime factorization of each number

24=2*2*2*3

20=2*2*5

to be a multiple of 24, the LCM must contain all of 24's prime factors

LCM=2*2*2*3 so far

to be a multiple of 20, the LCM must contain all of 20's prime factors; however, we don't use any factors that we already have because we want the least common multiple

we already have the two 2's so we only need the 5

LCM=2*2*2*3*5

LCM=120

another way...

20,40,60,80,100,120,140,160,...

24,48,72,96,120,144,168,192,...

what is the smallest number that appears in both sets of numbers ?

LCM=120 again