Question

question 1: the parking lot holds 176 cars.
a) 26 cars leave the lot. choose the calculation for the number of cars n remaining.
b) choose the mathematical model for the number of cars n remaining.
c) choose the mathematical model for the number of cars n remaining, leaving out the units.

another problem a) at which li grades papers per hour if it took him 5 hours to grade them.
select one
b) choose the mathematical model for the rate p at which li grades papers per hour if it took him h hours to grade them.
select one
c) write the mathematical model for the rate p at which li grades papers per hour if it took him h hours to grade them, leaving out the units.
(you can use \*\ for multiplication and \/\ for division.)

Explanation:

Step1: Identify remaining cars logic

To find remaining cars, subtract cars that left from total cars.

Step2: Match correct calculation

Total cars = 176, cars that left = 26. So the correct model is $N \text{ cars} = 176 \text{ cars} - 26 \text{ cars}$.

Step3: Define grading rate logic

Rate is total papers divided by time. Assume total papers = 1 (full set), so rate $P$ is $\frac{1}{\text{time}}$.

Step4: Generalize grading rate model

For time $H$ hours, the model without units is $P = 1/H$.

Answer:

a) N cars = 176 cars - 26 cars
b) (The corresponding model matching $P = \frac{1}{H}$ with units, e.g., $P \text{ papers/hour} = \frac{1 \text{ set of papers}}{H \text{ hours}}$)
c) $P = 1/H$