1. METRIC CONVERSION

2. What are Metric Conversions?
Sometimes we need to change from one measurement to another.
This is usually done because the unit that is used is either too big or too small for that type of measurement.

3. Sometimes the number is too big for the unit being measured.
525,568 millimeters
Sometimes the number is too big for the unit being measured.

4. Sometimes the number is too small for the unit being measuredkm
Sometimes the number is too small for the unit being measured

5. How Do We Fix This Problem?
We can correct these problems by doing a process called Metric Conversion. When you do a Metric Conversion, you are changing from one unit of measurement to another.

6. So How Do I Do A Metric Conversion?
We will be using 2 methods:
1) The Stair-step Method of Metric Conversion.
It requires two things; one, that you be able to count to 6, and two, that you know your left from your right.
2) The “Conversion Cross”
uses fractional equivalencies for conversions

7. The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters
base units
Deci-
Centi-
.01 Milli-
.001
Grams, liters,meters

8. A. SI Prefix Conversions
Symbol
Factor
mega- M
106
kilo- k
103
BASE UNIT
---
100
deci- d
10-1
move left
move right
centi- c
10-2
milli- m
10-3
micro- 
10-6
nano- n
10-9
pico- p
10-12

9. Metric Equivalents of Mass
1 kilogram (kg) = 1000 grams (g) 1 gram (g) = 1000 milligrams (mg) 1 milligram (mg) = 1000 micrograms (μg or mcg)
Household Examples
A pinch of salt
1 microgram
1 gram
1 milligram
1 kilogram

10. How Do I Use This? Start with the prefix of the first (known) unit.
Step up or down to get to the prefix of the desired unit.
Move the decimal the same direction & number of steps that were moved.
If there is only one letter in the unit of measurement, then you start or stop on the base unit step.

11. mm = ? m
Millimeters are a very small amount of distance. You would not want to measure a large distance in a very small unit.
To make the conversion, we start on the milli- step and go three steps to the left to get to the meter step. Therefore, the decimal in mm moves three places to the left, becoming m.

12. The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters
base units
Deci-
Centi-
.01 Milli-
.001
Grams, liters,meters

13. km = ? m
Kilometers are a fairly large unit of distance. You would not want to measure a small distance in a large unit, so we need to convert it to a smaller unit, the meter.
We would start on the Kilo- step and move three steps to the right this time, ending on the meter (base unit) step. Therefore, km becomes 6.54 m.

14. The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters
base units
Deci-
Centi-
.01 Milli-
.001
Grams, liters,meters

15. Method 2: Conversion Cross
Also called “factor-label”
The problem is solved by cancelling the units (or “factoring” them out)
cm3 g
= g
cm3

16. Conversion Cross Steps: 1. Identify starting & ending units.
2. Line up conversion factors so units cancel.
3. Multiply all top numbers & divide by each bottom number.
4. Check units & answer.

17. Conversion Cross 1 in = 2.54 cm 1
The key with the conversion cross is that the fractions must be equivalent.
Ex. 1m = 100 cm
60 sec = 1 minute
365 days = 1 year
1 in = 1
2.54 cm

18. B. Dimensional Analysis
How many milliliters are in 1.00 quart of milk?  qt mL
1.00 qt
1 L
1.057 qt
1000 mL
1 L
= 946 mL ÷

19. Conversion Cross 1.5 lb 1 kg 2.2 lb 1000 g 1 kg 1 cm3 19.3 g = 35 cm3
You have 1.5 pounds of gold. Find its volume in cm3 if the density of gold is 19.3 g/cm3.
Cross off units that cancel lb
cm3
1.5 lb
1 kg
2.2 lb
1000 g
1 kg
1 cm3
19.3 g
= 35 cm3
Each factor equals the conversion between the units