Belen can make 15 necklaces in 3 1/2 hours. How many can she make in one hour?

Belen can make 15 necklaces in 3 1/2 hours. How many can she make in one hour?

We set up a proportion of necklaces to time, where n is the number of necklaces Belen can make in 1 hour:
3 & 1/2 = 3.5, so we have:
15/3.5 = n/1

To solve this proportion, we type it in our search engine and we get:
n = 4.29 hours