Using the prime factor circles on Polypad can help students make meaning of finding common factors of numbers. Below are two videos showing some ways in which students could find common factors (including the greatest common factor) of 336 and 1260.

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Using the prime factor circles on Polypad can help students make meaning of finding common factors of numbers. Below are two videos showing some ways in which students could find common factors (including the greatest common factor) of 336 and 1260.