Question 15
A group of boys and girls went out to eat pizza on two consecutive days. In the restaurant where they went, the pizzas are cut into twelve equal pieces. Maria observed that on the first day each boy ate 7 pieces, and each girl 3 pieces. On the second day, each boy ate 6 pieces and each girl 2 pieces. Interestingly, on both days they ordered four pizzas that were completely consumed and then ordered another one, from which some pieces were left (that is, at least one piece was eaten and at least one piece was left over). How many boys and girls went to the pizzeria?