in the top left box there would be the number 8 because there are 8 boys who have pets
in the top right box there would be the number 5 because there are 5 boys who don’t have pets
in the bottom left box there would be the number 11 because there are 11 girls who have pets
in the bottom right box there would be the number 6 because there are 6 girls who don’t have pets