This graph shows the number of miles traveled by a train over a 5 hour trip. How fast is the train traveling?
A. 30 mph
B. 32.5 mph
C. 35 mph
D. 40 mph

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.