Anomalous Cancellation in Fractions

Did you know that you can just cancel out any common 3s, 6s, or 9s in the denominator and numerator of a fraction and leave it unchanged?

For example, 26 / 65 does equal 2 / 5. (Get rid of the sixes.)
And 163 / 326 does equal 1 / 2. (Get rid of the threes and the sixes.)

Does this seem too good to be true? We explain all in this video! (Watch till the end before becoming aghast!)

Anomalous Cancellation


    QUADRATICS, Permutations and Combinations, EXPLODING DOTS, and more!

    Written for educators - and their students too! - this website, slowly growing, takes all the content Tanton has developed in his books, videos, and workshops, and organizes it into short, self-contained, and complete, curriculum units proving that mathematics, at all points of the school curriculum, can be joyous, fresh, innovative, rich, deep-thinking, and devoid of any rote doing! Let's teach generations of students to be self-reliant thinkers, willing to flail and to use their common sense to "nut their way" through challenges, to assess and judge results, and to adjust actions to find success. (Great life skills!)


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