Answer:
The store marks up the fountain by adding $ 36.58 to its original cost, bringing its retail price to $ 402.42.
Explanation:
Given that a store pays $ 365.84 for a fountain, and then the store marks up the price by 10%, to determine the amount of the mark-up the following calculation must be performed:
365.84 x 10/100 = X
3,658.4 / 100 = X
36,584 = X
36.584 + 365.84 = 402.424
Thus, the store marks up the fountain by adding $ 36.58 to its original cost, bringing its retail price to $ 402.42.