Julia collects old watches. She owns 20 silver watches, and three times as many bronze watches. She decided to buy gold watches to add to her collection, a number that represents 10% of all the watches she owns. How many watches does Julia own after this purchase?
Thoughts? Step-by-step reasoning:
Julia owns 3 * 20 = 60 bronze watches. 60 + 20 = 80 total silver and bronze watches. 10% of all Julia's watches is 80 * 10 / 100 = 8 watches, and she decided to buy so many gold watches. So in total Julia is in possession of 20 + 60 + 8 = 88 watches.
Thus, the answer is 88.