my name is Christine
i am a student
the level of the question: middle(6)
 
my question is what is the lcm of 5,3,4,7,2

Hi Christine,

When finding the lcm you should fisrt write each number as the product of primes. In your list all the numbers are primes except 4 and 4 = 2².

I would start by proceeding through the list

The lcm of 5 and 3 is 5 3

Next look at 4 = 2². The lcm comstructed so far, 5 3 has no twos so to find the lcm of 3, 5 and 4 you need both twos. Hence

the lcm of 3, 5 and 2² is 5 3 2²

Next include 7. There are no sevens in the lcm so far so we need a 7.

The lcm of 3, 5, 2² and 7 is 5 3 2² 7

Finally the 2. 2 divided the lcm we have constructed already so

the lcm of 3, 5, 2², 7 and 2 is 5 3 2² 7 = 420

Penny

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