Question 380120
We are looking for the price of each notebook.  I'm going to call that n.

We bought 4 notebooks: 4n
The book was $44
We paid a total of $72

4 notebooks + book = total
4n + 44 = 72
To solve, first subtract 44 from each side:
4n+44-44=72-44
4n=28
Undo the multiplication by dividing by 4 on both sides:
{{{(4n)/4=28/4}}}
n=7
Thus, each of the 4 notebooks cost $7.
To double-check:
4*7+44=72
28+44=72
It checked correctly.