Recall that ratios are comparisons between two things. For example, you could make a ratio comparing the number of boys to girls because those are both things that you count. You could make a ratio of time spent on math and time spent on english, because those are comparisons of time.

When we make a comparison between things that are counted in different ways, then that is called a * rate* instead of a ratio. Find out about rate, unit rate and unit pricing to find out what they are useful for.

You will need to watch the videos for lesson 2. You can watch the whole playlist at once, or each of the videos separately:

- Video 1: What is a rate?
- Video 2: What is a unit price?
- Video 3: How to use unit prices and rates.
- Video 4: What is a unit rate?

Assignment:

- p60 #4, 5, 7, 8, 10, 12, 14, 15
- Bulk Mayonnaise Assignment (8L is a lot, but maybe Dan owns a restaurant...ever think of that?)

Things you should know after today:

- How is a rate different from a ratio?
- How can unit price be used to determine a better buy
- How can you calculate a unit rate
- How can unit price and unit rate be used to solve a problem