Question

The number of books in a classroom library is 17 more than 3 times the number of students in the class. If 5students are absent, each student can borrow exactly 4 books. How many students are in the class?

Answer 1

Number of books: B

Number of students: S

We know that the classroom library has 17 more books than 3 times the number of students. Then:

`B=3S+17`

Additionally, if 5 students are absent, each student can borrow exactly 4 books. Then:

`B=4(S-5)=4S-20`

Now, using these two results:

`\begin{gathered} 3S+17=4S-20 \\ 17+20=4S-3S \\ 37=S \end{gathered}`

There are 37 students in the class.