Grade
3

Guess My Rule: Number Sorting

What are the rules for the circles?

In the red circle: 16, 8, 12, 24, and 4. In the blue circle: 5, 35, 10, 25, and 30. In the intersection of the red and blue circles: 20, 40. Outside the circles: 42, 14, 6, 9, 21, and 18.
  1. Some numbers belong in the circles, and some do not.
    What is the rule to be in the red circle?
    What is the rule to be in the blue circle?
    What is the rule to be in both circles?
  2. Write at least one more number that belongs only in the red circle.
  3. Write at least one more number that belongs only in the blue circle.
  4. Write at least one more number that belongs in the intersection of the two circles.
  5. Will there ever be an odd number in the intersection of the two circles? Why?

What do 16 and 20 have in common? Where do you see them on a multiplication table?

What do 15 and 25 have in common? Where do you see them on a multiplication table?

Make your own rules about numbers. You can use the circles below or draw your own.

If possible, show some examples that belong inside each circle and some examples that don’t belong in either circle.

blank red and blue circles that overlap, with text, 'The rule for the red circle is:' and 'The rule for the blue circle is:'
Printable Version

Google doc for printing and copying

Reference for Educators

Sample problems and solutions