Junior Prom

There are 120 juniors in the current class. Of those, 66 are going to the junior prom. The same number (66) of juniors are going out to dinner that evening, including 48 of those going to the prom. How many juniors are neither going to the prom nor going out to dinner?

Frat Classes

In a fraternity with 30 members, 18 take mathematics, 5 take both mathematics and biology, and 8 take neither mathematics nor biology. How many take biology, but not mathematics.

Math Classes

Thirty elementary teachers were asked which high school courses they appreciated: algebra or geometry. Seventeen appreciated algebra and 15 appreciated geometry; of these. 5 said that they appreciated both. How many appreciated neither.

Thirsty?

Lemonmobiles are available with two possible options: radio and air conditioning. The owner of the Lemonmobile Emporium is studying a recent inventory of his lot, which shows

50 Lemonmobiles on hand in all

25 Lemonmobiles have radios

13 have both options, radios and air conditioning

15 have neither option

How many of the Lemonmobiles on hand have air conditioning? How many of the Lemonmobiles on hand have radios but no air conditioning?