Hello there! We can solve this question by writing and solving a proportion. Set it up like this:
9/x = 3/100.
This is because 9 is 3% of x number of stores and percents are parts of 100. Setting it up like this will help us get the correct answer. Cross multiply the values . 9 * 100 is 900 and 3 * x = 3x. You get 900 = 3x. Now, divide each side by 3 to isolate the x. 3x/3 cancels out the x. 900/3 is 300. There. x = 300. 9 stores is 3% of 300 stores.