Using proportions, the selling prices are given as follows:
1. $46.92.
2. $15.29.
3. $17.16.
4. $20,280.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
To find the selling prices, we have to multiply the original prices by either 1.02(2% sales tax) or 1.04(4% sales tax), hence they are given as follows:
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