On Fridays, Harry's school serves a choice of hamburgers or pizza for lunch. 60% of the sixth grade class ate pizza this Friday. If 36 sixth grade students ate pizza, how many students are in the sixth grade?

Assume that the number of students in grade six is n.

We are given that 60% of the students ate the pizza and that the total number of students who ate pizza is 36.

This means that 36 students represent 60% of the total number of students.

In other words:

60% * n = 36

0.6n = 36

n = 36 / 0.6

n = 60

Based on the above calculations, the total number of students in grade six is 60 students