Common Denominators with Cuisenaire® Rods

To find a common denominator for fractions like 1/2 and 1/3, use a red rod and a light green rod to represent the denominators 2 and 3. Next, create a multiple train by stacking copies of each rod color. When the trains are the same length, the train is a common multiple of the two denominators. The first common denominator of 1/2 and 1/3 is 6. Notice that 12 is also a common denominator of the fractions 1/2 and 1/3. Because 6 is the smallest multiple of the denominators, it is the least common denominator.

Common Denominators using the Brainingcamp Cuisenaire® Rods virtual manipulative.

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Brainingcamp virtual manipulatives can be used anywhere with no setup, cleanup, or lost parts. They are highly effective at engaging today’s digital learners and helping them bringing abstract math concepts to life.


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