1. Metric System

2. A prefixes plus a base unit makes up the metric system
The metric system is based on a base unit that corresponds to a certain kind of measurement
Base unit for length = meter
Base unit for volume = liter
Base unit for mass = gram
A prefixes plus a base unit makes up the metric system
Metric prefixes:
Example:
Centi + meter = Centimeter
Kilo + liter = Kiloliter

3. The three prefixes that we will use the most are:
kilo
centi
milli
kilo-
hecto-
deca-
Base Unit
Meter
Gram
Liter
deci-
ceni-
milli-

4. If you needed to measure length you would choose meter as your base unit
Length of a tree branch
1.5 meters
Length of a room
5 meters
Length of a ball of twine stretched out
25 meters

5. But what if you need to measure a longer distance, like from your house to school?
Let’s say you live approximately 10 miles from school
10 miles = 16,093 meters
16,093 is a big number, what if we could convert it to a more manageable number?
16,093 meters = kilometers (or 16.1 if rounded to 1 decimal place)

6. These prefixes are based on powers of 10. What does this mean?
From each prefix every “step” is either:
10 times larger or
10 times smaller
This is 10 times larger than this

7. millimeters
Centimeters are 10 times larger than millimeters so it takes 10 millimeters to equal the same distance as 1 centimeter
centimeter

8. For each “step” to the right, you are multiplying by 10
For example, let’s go from the base unit liters to centiliters
Centi is 2 steps to the right of our base unit.
If we have 1 liter of soda and want to know how many centiliters it is we have to do a little conversion.
1 liter x 10 x 10 = 100 centiliters (10 x 10 because centi is 2 steps away and each step to the right means you multiply by 10.

9. Another way to move within the metric system is by moving the decimal point one place for each “step” desired
Example: convert 1 meter to centimeters
1 meter = 10 decimeters = 100 centimeters or
1.00 meter = 10.0 decimeters = 100. centimeters

10. Now let’s try moving left.
Lets look at our example of living 16,093 meters from school and change it from meters to kilometers:
Since we are moving left we need to divide by 10 for each step we take.
16,093 meters ÷ 10 = 1,609.3 decameters ÷ 10 = hectometers ÷ 10 = kilometers

11. Or we could move our decimal the correct number of place values to the left.
16,093 meters = 1,609.3 decameters = hectometers = kilometers
So for every “step” from the base unit to kilo, we moved the decimal 1 place to the left (the same direction as in the diagram below)

12. If you move to the left in the diagram, move the decimal to the left
If you move to the right in the diagram, move the decimal to the right

13. Lets convert from centimeters to kilometers
400,000 centimeters = ? Kilometers
Kilometers is 5 steps to the left.
You can either divide by 10 five times or move the decimal point 5 place values to the left. Either way you will get the same answer.
400,000 centimeters = 4 kilometers

14. Practice 3 meters = ______ centimeters .4 liters = ______ deciliters
600 milligrams = _______ grams
5 kilometers = __________ hectometers
70 centimeters = _________ meters
900 deciliters= _______ milliliters
A python caught in Florida measured 600 centimeters long. How many meters long was the snake?
Faith weighed 5 kilograms at birth. How many grams did she weigh?