1. MODULE A - 5
Conversion and Cancel

2. OBJECTIVES At the end of this module, the student will be able to…
Given a mathematical problem requiring conversion between measurements systems and the appropriate conversion factors, derive the correct answer.
Given a mathematical problem requiring conversion within the metric system, derive the correct answer.

3. Setting up a conversion problem
What is a unit of measure?
Attached to a number
Indicates how something is being measured
EXAMPLES:
Pounds or Grams
Inches or Meters
Gallons or Liters

4. Setting up a conversion problem
Convert: 100 lbs to ___ kgs
Units of measure

5. Setting up a conversion problem
What is a “Given” and an “Unknown”?
Given is the starting value or quantity.
Unknown is answer.
EXAMPLES:
Convert: 100 pounds to ___ kilograms
Convert: 100 milliliters to ___ Liters

6. Setting up a conversion problem
Convert: 100 lbs to ____ kgs
UNKNOWN VALUE
GIVEN VALUE

7. Setting up a conversion problem
(Given) (Conversion factor) (Answer)
Problems requiring conversions will be solved easier when a standardized procedure of set-up and solution is used.

8. Setting up a conversion problem
Set the problem up like you are multiplying two fractions.
The unit of measure in the given value must cancel out.
The remaining unit of measure will be in the answer.

9. The Conversion Problem
(Conversion factor)
(Given)
(Answer)
Given (given) x Unknown (unit) = Unknown (looking for)
Given (unit)
* Convert: 100 lbs to kgs
* Set up the problem:
1. lbs is the Given value or starting value
2. kg is the Unknown or what you are looking for (end)

10. Conversion Factor GIVEN: 100 pounds UNKNOWN: ? Kg
Convert: lbs to kgs:
GIVEN: 100 pounds
UNKNOWN: ? Kg
CONVERSION FACTOR: 2.2 lbs = 1 kg
* Place the conversion factor into the formula so the Given units will cancel out .

11. Conversion from one system to another
Conversion Factor Samples:
2.2 lbs per kg
0.45 kg per lb miles per kilometer
454 gm per lb qts. per liter
28.3 gm per ounce liters per gallon
473 ml per pint
39.37 inches per meter
2.54 cm per inch
inches per cm
* Conversion factors also provided in Lesson #4 handout

12. Conversion Practice Convert: 500 kgs into lbs
Conversion factor: 2.2 lbs = 1 kg

13. Given x Unknown = Unknown 1 Given
Conversion Practice
(Given) (Conversion factor) (Answer)
Given x Unknown = Unknown
Given
Convert : 50 cm to inches
Conversion factor: cm per inch
50 cm x ____ in = ______ in = __________ in cm

14. Conversion Practice Given x Unknown = Unknown 1 Given
Convert : 12 inches to centimeters
Conversion factor: cm = inch
_____ in x ____ cm = ______ cm = _________cm in

15. 20 L x ______ gallon = ______ gallon = _____ gallon
Conversion Practice
Given x Unknown = Unknown
Given
Convert: 20 liters to gallons
Conversion factor: liters per gallon
20 L x ______ gallon = ______ gallon = _____ gallon L

16. Conversion Practice
Convert: 26 gallons to L
Conversion factor: liters per gallon

17. Conversion within the metric system.
You will need a copy of the metric table to perform these calculations

18. Conversion within the metric system.
Use the same formula:
Given x Unknown = Unknown
Given
(Given) (Conversion factor) (Answer)

19. Metric Conversion One place = 10 Two places = 100 Three places = 1000
Count the number of places you are moving on the metric table to determine the conversion factor.
Each is a multiple of 10.
One place = 10
Two places = 100
Three places = 1000

20. Metric Conversion
Determine where that conversion factor should be placed in the formula.
Ask yourself “Which is larger, the Given unit of measure or the Unknown unit of measure?”
The larger number gets 1 and the smaller gets the conversion factor.

21. Metric Conversion – Set up
Given x Unknown = Unknown
Given
Convert: 50 mL to Liters
50 mL x ____ L = ______ L = _____
____ mL
(Given) (Conversion factor) (Answer)

22. Metric Conversion – Determine the Factor
Convert: 50 mL to Liters
Determine conversion factor by counting places:
L dL cL mL = 3 places
* mL is 1000 times smaller than a Liter because it is to the right of the Liter 3 places

23. Metric Conversion – Insert the Factor
Convert: 50 mL to Liters
50 mL x __1__ L = _______ L = ______ mL
Place conversion factor into formula with larger unit receiving the “1”
mL is 1000 times smaller than a 1 Liter

24. Metric Conversion - Solve
Given x Unknown = Unknown
Given
Convert: 30 L to mL
____ L x _____mL = ______ mL = ____
____ L
Liter is larger so it gets the “___” and mL is ___ times smaller.

25. Practice - Metric Conversion
Convert from or to the basic unit:
25 Liters to mL = ______________
50 mL to Liters = _______________
45 Liters to mL = _______________
6 ML to Liters = ________________
(remember M = Mega)

26. Practice - Metric Conversion
Convert across or to sides of basic unit:
25 mL to mL = ______________
45 kg to Mg = _______________

27. ASSIGNMENTS Sibberson Math Book: Chapter 1
Read Page 1 – 3
Do First & Second Sample Set - pgs 2 & 3
Practice problems – page 7, #1 – 15
Continue work on objectives.