Venn Diagrams & Counting Sets

How the lesson starts: Venn Diagrams & Counting Sets

Pet Day!
It's Pet Day in Miss Juniper's class! Some kids have a dog. Some have a cat. Some kids have both! And some have neither. Let's sort it all out with a Venn diagram.
Four places to sort
A Venn diagram has two circles that overlap. Set A is dog owners. Set B is cat owners. 7 kids have a dog only. 3 kids have both, so they go in the overlap. 5 have a cat only. 5 have neither, outside the circles.
Sort the number tags
Every pet wears a number tag. Set A is even numbers. Set B is multiples of 3. Ask two questions for each tag. 12: even? Yes. Multiple of 3? Yes. So 12 goes in both! 4 is even only. 9 is a multiple of 3 only. 5 is neither.