For this case, the first thing we must do is define variables.
We have then:
x: number of packs of 4
y: number of notebooks
The equation modeling the problem is given by:
\(y = 4x
\)
Three packs of notebooks are sold.
Therefore, for x = 3 we have:
\(y = 4 (3)
y = 12
\)
As the number of notebooks are 28, then the remaining amount is:
\(28-12 = 16
\)
Answer:
There are 16 notebooks left
