Mini Math Lesson
For use with the February 2010 issue, pages 12–13.
to write a fraction
in simplest form
✔ Find the greatest common
factor (GCF) of the numerator
and denominator.
✔ Divide both the numerator
and denominator by the GCF.
4
Example: What is __
​    ​ in
10
simplest form?
Factors of 4: 1, 2, 4
Factors of 10: 1, 2, 5, 10
✔ Divide:
4÷2=2
10 ÷ 2 = 5
The GCF of 4 and 10 is 2.
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