1. Estimate using large paper clips.
EXAMPLE 1
Using Metric Units of Length
Estimate the length of the bandage by imagining large paper clips laid next to it. Then measure the bandage with a metric ruler to check your estimate.
STEP 1
Estimate using large paper clips.
About 5 large paper clips fits next to the bandage, so it is about 5 centimeters long.

2. EXAMPLE 1
Using Metric Units of Length
Estimate the length of the bandage by imagining large paper clips laid next to it. Then measure the bandage with a metric ruler to check your estimate.
STEP 2
Measure using a ruler.
Each centimeter is divided into tenths, the bandage is 4.8 centimeters long.

3. Find the mass of the apples.
EXAMPLE 2
Measuring Mass
Find the mass of the apples.

4. You can use the following benchmarks to estimate mass.
EXAMPLE 2
Measuring Mass
Mass Benchmarks
You can use the following benchmarks to estimate mass.
1 milligram grain of sugar
1 gram small paper clip
1 kilogram textbook

5. Copy and complete using the appropriate metric unit:
EXAMPLE 3
Using Metric Units of Mass
Copy and complete using the appropriate metric unit:
The mass of a CD is ? .
The mass of a CD is greater than the mass of 16 grains of sugar (16 mg), and it is less than the mass of 16 textbooks (16 kg). Because a good estimate for the mass of a CD is 16 paper clips, the appropriate metric unit is grams.
ANSWER
The mass of a CD is 16 grams.

6. between 0 kg and 1 kg ( at about 0.75 kg )
GUIDED PRACTICE
for Examples 1, 2 and 3
1. What If? Suppose you estimate with paper clips that a larger bandage is about 8 centimeters long. Is its actual length more likely to be 7.2 centimeters or 7.7 centimeters?
ANSWER
7.7 cm
2. What If? Suppose there were only 3 apples on the scale in Example 2. Describe where the pointer would point relative to the 1 kg mark.
ANSWER
between 0 kg and 1 kg ( at about 0.75 kg )

7. Copy and complete using the appropriate metric unit.
GUIDED PRACTICE
for Examples 1, 2 and 3
Copy and complete using the appropriate metric unit.
3. The mass of a baby is 4 ? .
ANSWER kg
4. The mass of a tack is ? .
ANSWER mg