Everyone in the class was supposed to bring at least pencil with them to the exam. There are 30 people in the class. If 5 people brought 1 pencil, 18 brought 2, and 6 brought 3 or more, how many people forgot to bring a pencil?	Choose the correct option.
A) 0
B) 1
C) 2
D) 3
E) 4
As the categories do not overlap, you can simply subtract the different category counts from the class total to get the answer: 20-5-18-6=1. The answer is 1: 1.
<result>B</result>
Everyone in the class was supposed to bring at least pencil with them to the exam. There are 30 people in the class. If 5 people brought 1 pencil, 18 brought 2, and 6 brought 3 or more, how many people forgot to bring a pencil?