Final answer:
The unit rate for (a) 20 miles every 3 hours is 6.67 miles per hour, and for (b) 2 dollars per day is 2 dollars per day. Unit rates are used to compare a quantity to one unit of another and help determine how reasonable calculations are.
Step-by-step explanation:
The unit rate is the measure of the quantity of one thing in comparison to one unit of another thing. In this context, we're looking at how much distance is covered per unit of time or how much money is spent per unit time.
For question (a), the task is to find how many miles are traveled in one hour if 20 miles are traveled every 3 hours. To calculate the unit rate, we divide the total distance by the total time:
- 20 miles ÷ 3 hours = 6.67 miles per hour, which is the unit rate.
For question (b), determining the unit rate if 2 dollars are spent per day is straightforward:
- The unit rate is simply 2 dollars per day since it is already expressed per one unit of time (one day).
It is essential to check if the unit rates calculated are reasonable. For example, if a car travels 10 km in a third of an hour (20 minutes), it would travel three times that distance in a full hour, which seems reasonable and can help confirm the accuracy of unit rate calculations.