Answer: There are 9 banners that can be made from 12 sections of plastic.
Explanation:
Since we have given that
Number of banners which require
sections of the plastic = 1
We will use the " Unitary method", we get
Number of banners which require 1 section of the plastic is given by

Number of banners which requires 12 sections of the plastic is given by

Hence, there are 9 banners that can be made from 12 sections of plastic.