The rate is defined as the ratio between two different quantities. The quantities such as miles, centimeters, minutes, seconds and so on. Ratio is the quantitative comparison between the given quantities. For the quantities the unit rate is calculated by the ratio of two different quantities are compared to a unit measure of one of the quantity. Some examples how the unit rates are expressed are miles per hour written as miles/hour; liters per seconds written as liter/sec.
Example 1: Rachel spent $ 40 dollars in 2 hours. At that rate how much will she spend in the next 5 hours?
Solution: Here first find the unit rate.
Rachel spends $ 40 in 2 hours of time. This can be written as:
Unit rate = 40 dollars/ 2 hours = 40/2 dollars per hour = 20 dollars per hour.
Hence, Amount spent / Time taken = 20.
In the next 5 hours: Amount of dollars spent/ 5 = 20.
Money spent = 20 x 5 = 100.
Therefore, Rachel will spend $ 100 in the next 5 hours.
Question: Multiple choice question (Pick the correct option.)
What is the unit rate for running 20 miles in 5 hours? ------ Miles per hour?
a) 5 b) 3 c) 4 d) None of these.
Correct answer: option c
.Explanation: Here we have 20 miles covered in 5 hours.
For the unit rate ---- miles per hour, needs to be found.
Therefore, 20 miles/ 5 hours = 4 miles / 1 hour.
Hence unit rate = 4 miles per hour.