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 Question from Aiyanna, a student: What is The Lcm Of 3,7,and 8 Because my Teacher gave me That and he didnt even know the answer.... I Worked and worked but I Couldnt Find It.....

We have two responses for you

Aiyanna,

Let's find the lcm of 2, 5, and 6 instead.

The positive multiples of 2 are 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, ....
The positive multiples of 5 are 5, 10, 15, 20, 25, 30, 35 ...
The positive multiples of 6 are 6, 12, 18, 24, 30, ...

The common multiples of 2, 5, and 6 are the numbers that appear in all three lists: 30, 60, 90, ...
The least common multiple is the smallest number that is all three lists. This is 30.

Victoria

What you are trying to find is the smallest number into which you can divide 3, 7 and 8. You should note that 3, 7 and 8 don't share any divisors. Thus to get a number that 7 and 8 divides you need to multiply them, i.e. it's 56. Now what can you do with the 3 and your new number 56?

Your teacher should know this or they're not really teaching you math.

Penny

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