Using proportions, it is found that their bill before adding the tip was of $27.48.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
They paid a 20.2% tip, hence 120.2% = 1.202 of the price x is equals to $33.03, hence the bill before the tip is found as follows:
1.202x = 33.03
x = 33.03/1.202
x = $27.48.
More can be learned about proportions at https://brainly.com/question/24372153
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