A 12-ounce bottle of shampoo lasts Enrique 16 weeks. How long would you expect an 18-ounce bottle of

A 12-ounce bottle of shampoo lasts Enrique 16 weeks. How long would you expect an 18-ounce bottle of the same brand to last him?

Set up a proportion of ounces to weeks were w is the amount of weeks an 18-ounce bottle will last:
12/16 = 18/w

We type this proportion in our search engine to solve for w and we get:
w = 24