Answer:
The answer is 6.6$
Step-by-step explanation:
Firstly, you have to realize that the cost of a notebook is directly proportional to the amount of notebook you want.
So, the relation is:
Let
x=total cost of notebooks
y=amount of notebooks
\(\frac{x}{y} =k\)
Where k is a constant
Therefore, the cost of 10 notebooks is:
Let z=total cost of 10 notebooks
\(\frac{1.98}{3}=\frac{z}{10}\\z=\frac{1.98*10}{3} \\z=6.6\\\)