All Lesson Plans

Common Factors

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.

Finding Common Factors Using Prime Factor Circles

Finding Common Factors Using Venn Diagrams

Further Reading

Greatest Common Factors - Divisibility and Primes - Mathigon
Reading time: ~10 min Reveal all steps An architect is planning the floor for a large courtyard that measures 18m by 30m. She wants it to be covered in quadratic tiles, without any gaps or overlaps along the sides. What is the largest size of squares she can use?