If Joanne read 84 pages in 4 hours. Then the unit rate for Joanne is 21 pages per hour.
The rate is the ratio of the amount of something to unit time.
For example - If the speed of the car is 20 km/h which means the car travels 20 km in one hour.
Joanne read 84 pages in 4 hours.
Then the rate of the Joanne will be
[tex]\rm Rate = \dfrac{84}{4}\\\\Rate = 21[/tex]
More about the rate link is given below.
https://brainly.com/question/14731228
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