Lowest common multiple of two numbers

Difficulty Stretch · Set k1fmk9

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1
What is the least common multiple of 15 and 16?
2
What is the least common multiple of 38 and 19?
3
What is the least common multiple of 27 and 34?
4
What is the least common multiple of 5 and 36?
5
What is the least common multiple of 34 and 10?
6
What is the least common multiple of 13 and 38?
7
What is the least common multiple of 7 and 34?
8
What is the least common multiple of 19 and 4?
9
What is the least common multiple of 16 and 31?
10
What is the least common multiple of 38 and 14?
11
What is the least common multiple of 39 and 6?
12
What is the least common multiple of 24 and 30?
13
What is the least common multiple of 20 and 37?
14
What is the least common multiple of 21 and 36?
15
What is the least common multiple of 23 and 8?
16
What is the least common multiple of 19 and 15?
17
What is the least common multiple of 30 and 27?
18
What is the least common multiple of 4 and 26?
19
What is the least common multiple of 38 and 6?
20
What is the least common multiple of 34 and 9?

What is in this set

The numbers in this set run from 4 to 40.
63% of them share no factor at all.
37% of them share a factor.
A careful solution takes 3 written steps on average.
The mistake this set invites most often, in 100% of the problems: that is the greatest common factor — a common multiple is never smaller than either number.
Answers are a whole number.

Drawing 240 problems from this page produced 220 different ones, 92% — so a sheet of 20 is a new sheet almost every time.

The same skill, harder or easier

We would put this in front of a grade 6 class. That is our judgement, not a standard, and it is printed here so you can disagree with it. Everything else we put in that year.