Today in class we talked about unit rates. A unit rate is a comparison between two numbers.
For example if you could have 120 minutes of fun for $23 or 60 minutes for $11 which one would you pick? You would pick the 60 minutes for $11 because half of 120 is 60 so half of $23 is $11.50. In that case you would rather spend $11 thanhave to spend $11.50.
Another example is driving 21 miles in 30 minutes or 80 miles in 100 minutes. The answer is 21 miles in 30 minutes. If you look at it in fractions 21/30 simplifies to 7/10 and 80 miles in 100 minutes simplifies to 8/10 so the first one is the shorter drive.