1. AKA Unit- factor method
Dimensional Analysis
AKA Unit- factor method

2. Solve the following…
A car manufacturer needs to calculate the number of tires needed to produce a new line of race cars.

3. The manufacturer knows that each car will require 4 wheels and the goal is to have a production of 3,300 new cars by the end of the fall.

4. How many tires does the manufacturer need to order to build his new series of sport cars?

5. Answer: 13,200 tires Congratulations!
You just completed a dimensional analysis problem.

6. How did you solve this problem?
You might not realize it but you used a conversion factor to solve this problem.

7. You know that for every car you need 4 tires:
1 car or 4 tires
4 tires 1 car
We call these conversion factors.

8. Conversion Factors
Conversion factors allow you to go from one factor to another.
In this case the conversion factor allows us to go from the number of cars being produced to the number of tires needed for the production.

9. Cars cross out and we’re left with: 3,300 X 4 tires = 13,200 tires
Let’s show our work…
3,300 cars X 4 tires =
1 car
Cars cross out and we’re left with:
3,300 X 4 tires = 13,200 tires

10. Let’s practice!
A new drug has a dosage of 2.3 mL for every 1 pound of patient’s body weight. If you have a patient who weights 198 lbs, how much drug should you give them?

11. LET’S SHOW OUR WORK… 2.3 mL X 198 lb = lb
Pounds cross out and we are left with:
2.3 mL X 198 = mL

12. LET’S PRACTICE SOME MORE…
If you have a 1200g container which contains 50 apples and each apple averages a mass of 75 grams. What is the total mass of the container?

13. SOLUTION 75 g X 50 apples = 1 apple
Apples cross out and we are left with:
75 g X 50 = 3750 g

14. Are we done? Don’t forget to add the mass of the basket.
Mass of container + Mass of apples =
1200g g = 4950 g