N S O S E L Measuring in Metric Units
Goal: Measure and estimate using metric units.
Vocabulary The metric system is a decimal system of Metric system: measurement. The metric system has units for length, mass, and capacity.
The meter (m) is the basic unit of length in the metric Metric units system. Three other metric units of length are the of length: millimeter (mm), centimeter (cm), and kilometer (km).
Mass: Mass is the amount of matter that an object has.
The gram (g) is the basic metric unit of mass. Two Metric units other metric units of mass are the milligram (mg) of mass: and the kilogram (kg).
Capacity is a measure of the amount that a container Capacity: can hold.
The liter (L) is the basic metric unit of capacity. Two Metric units other metric units of capacity are the milliliter (mL) of capacity: and the kiloliter (kL).
Benchmarks 1 millimeter is about the thickness of a dime. 1 centimeter is about the width of a large paper clip. 1 meter is about the height of the back of a chair. 1 kilometer is about the combined length of 9 football fields. 1 milligram is about the mass of a grain of sugar. 1 gram is about the mass of a small paper clip. 1 kilogram is about the mass of a textbook. 1 millimeter is about the capacity of an eyedropper. 1 liter is about the capacity of a large water bottle. 1 kiloliter is about the capacity of 8 large trash cans.
38 | Chapter 2 Notetaking Guide EXAMPLE 1 Using Metric Units of Length Estimate the length of a key by imagining paper clips laid next to it. Then measure the key with a metric ruler to check your estimate.
Solution WATCH OUT! A typical metric ruler 1. About 4 large paper clips 2. Measure using a ruler. allows you to measure fit next to the key, so it is about only to the nearest 4 centimeters long. tenth of a centimeter.
cm 1234
Each centimeter is divided into tenths , so the key is
3.9 centimeters long.
EXAMPLE 2 Measuring Mass Find the mass of the plastic model of bananas. Each gram is divided into tenths , so the mass of the model is 18.3 grams . 19 g 18 g 0 g 2 g 16 g 4 g 18 g
14 g 6 g 12 g 8 g 10 g 17 g
EXAMPLE 3 Using Metric Units of Mass Copy and complete the statement using the appropriate metric unit: The mass of a computer monitor is 5____? . The mass of a computer monitor is greater than 5 grains of sugar
5 mg , and is also greater than the mass of 5 paper clips 5 g .
Because a good estimate for the mass of a computer monitor is 5 textbooks , the appropriate metric unit is kilograms .
Answer: The mass of a computer monitor is 5 kilograms .
Lesson 2.6 Measuring in Metric Units | 39 Guided Practice Complete the following exercise.
1. Estimate the length of a video cassette in centimeters. Then use a metric ruler to check your estimate.
15 cm; 15.4 cm
Copy and complete the statement using the appropriate metric unit.
2. The mass of a cat is 4 ____. ? 3. The mass of a rubber band is 175 ____.?
kg mg
EXAMPLE 4 Measuring a Liquid Amount Find the amount of liquid in the measuring cup.
200 mL 200 ml 190 mL Each 100 mL is divided into tenths, so the liquid is 180 mL 100 ml 170 mL at the 180 mL level. 160 mL
Answer: The measuring cup contains 180 milliliters of liquid.
EXAMPLE 5 Standardized Test Practice What is the most reasonable capacity of a bucket? A 6 L B 65 mL C 75 L D 2 kL Solution Both 75 L 75 large water bottles and 2 kL 16 large trash cans
would overfill a bucket. Using 65 mL 65 eyedroppers would be too
little. That leaves 6 L 6 large water bottles , which seems reasonable.
Answer: The most reasonable capacity of a bucket is 6 L . The correct answer is A . ABCD
40 | Chapter 2 Notetaking Guide Guided Practice Match the object with the appropriate capacity.
1. Spoon 2. Hot tub 3. Drinking glass A. 1.3 kL A. 1.3 kL A. 1.3 kL B. 250 mL B. 250 mL B. 250 mL C. 2 mL C. 2 mL C. 2 mL
CAB
Lesson 2.6 Measuring in Metric Units | 41