Taking out a common factor

Difficulty Starter · Set 9avqxh

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1
Take out the greatest common factor of20x+8— what is it?
2
Take out the greatest common factor of20x+16— what is it?
3
Take out the greatest common factor of20x+25— what is it?
4
Take out the greatest common factor of4x+6— what is it?
5
Take out the greatest common factor of6x+9— what is it?
6
Take out the greatest common factor of16x+12— what is it?
7
Take out the greatest common factor of4x+10— what is it?
8
Take out the greatest common factor of10x+4— what is it?
9
Take out the greatest common factor of20x+25— what is it?
10
Take out the greatest common factor of12x+15— what is it?
11
Take out the greatest common factor of15x+12— what is it?
12
Take out the greatest common factor of12x+9— what is it?
13
Take out the greatest common factor of15x+9— what is it?
14
Take out the greatest common factor of16x+12— what is it?
15
Take out the greatest common factor of10x+6— what is it?
16
Take out the greatest common factor of15x+12— what is it?
17
Take out the greatest common factor of20x+8— what is it?
18
Take out the greatest common factor of12x+15— what is it?
19
Take out the greatest common factor of20x+12— what is it?
20
Take out the greatest common factor of8x+10— what is it?

What is in this set

The numbers in this set run from 4 to 25.
A careful solution takes 2 written steps on average.
The mistake this set invites most often, in 100% of the problems: 8 does not divide 12.
Answers are a whole number.

Drawing 240 problems from this page produced 40 different ones, 17% — so a sheet of 20 will come back to a problem you have seen — there are only so many sensible ones of this kind.

The same skill, harder or easier

We would put this in front of a grade 8 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.