Ronald ate 1/3 of a pizza for lunch. The next day he had part of the pizza for a snack. In total, he ate 1/2 of the pizza. Ronald drew a circle, with part of it shaded, to represent the fraction of the pizza that he ate for his snack. Which diagram did Ronald draw to represent the part of the pizza he had for his snack?

no idea which diagram, but 1/3 + 1/6 = 1/2