1. 1-5 Measuring in Metric Units
You’ll Learn: To use and convert metric units of measure.

2. Metric Units Type Unit Reference Example Length Millimeter (mm)
Centimeter (cm)
Meter (m)
Kilometer (km)
About the thickness of a dime
About the width of your little finger
About the distance from a doorknob to the floor
About the length of 11 football fields
Capacity
Milliliter (mL)
Liter (L)
A small spoon holds about 5 mL
A little more than 1 quart
Mass
Milligram (mg)
Gram (g)
Kilogram (kg)
About the mass of a mosquito
About the mass of a paper clip
About the mass of a bunch of bananas

3. Metric Length Relationships
Unit
Kilo-meter
Hecto-meter
Deca-meter
meter
Deci-meter
Centi-meter
Milli-meter
Symbol km hm
dam m dm cm mm
Value
1,000m
100m
10m 1m
0.1m
0.01m
0.001 m

4. Choosing a Reasonable Estimate
When trying to measure using the metric system, it is important to estimate so that you can accurately choose a tool to measure.
Choose a reasonable estimate:
Height of a classroom
3 cm 3 m 3 km
Mass of a bag of flour
2.3 mg 2.3 g 2.3 kg

5. Choose a reasonable estimate and explain your choice.
Capacity/Volume of a soup bowl:
180 mL 180 L 180 kL
Mass of a Butterfly:
500 mg 500 g 500 kg
Height of an oak tree:
22 cm 22 m 22 km

6. Multiplying to Change Units
You can change a measurement from one unit to another by finding the relationship between the two units and multiplying.

7. Metric Relationships Unit Kilo-meter Hecto-meter Deca-meter meter
Deci-meter
Centi-meter
Milli-meter
Symbol km hm
dam m dm cm mm
Value
1,000m
100m
10m 1m
0.1m
0.01m
0.001 m
Unit
Kilo-gram
gram
Milli-gram
Symbol kg g mg
Value
1,000g 1g
0.001 g
Unit
liter
Milli-liter
Symbol L mL
Value 1L
0.001 L

8. Step 1
Decide if the conversion you are trying to do is going from a larger unit to a smaller unit or from a small unit to a larger unit.
mL to L
km to m
cm to m

9. Step 2 Decide how many of the missing unit fits into the known unit.
245 mL = _____ L
1 mL = L
Hint:
If you are going from big to small, your missing unit value should be a WHOLE number.
If you are going from small to big, your missing unit value should be a DECIMAL.
mL is smaller than L
Small to Big  We use a decimal.

10. Step 3
Once you decide your relationship, multiply by the missing value.
245 x = L

11. Put it all together! Change 245 milliliters to liters.
245 mL = ____L
1 mL = L
245 x = 0.245
Check for Reasonableness:
A milliliter is less than a liter. So, the number of liters should be less than the number of milliliters < 245, so the answer is reasonable.