Holt CA Course 1

4-9 Metric Measurements

AF2.1 Convert one unit of measurement to another (e.g., from feet to miles, from centimeters to inches).

California Standards

Holt CA Course 1

4-9 Metric MeasurementsYou can use the following benchmarks to help you understand millimeters, grams, and other metric units.

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Holt CA Course 1

4-9 Metric Measurements

Choose the most appropriate metric unit for each measurement. Justify your answer.

A. The amount of water a runner drinks each day

Meters—The length of a boat is similar to the length of several doorways.

Liters—The amount of water a runner drinks each day is similar to the amount of water in a large water bottle.

Kilograms—The mass of a car is similar to the mass of several hundred textbooks.

Example 1: Choosing the Appropriate Metric Unit

C. The mass of a car

B. The length of a boat

Holt CA Course 1

4-9 Metric Measurements

The prefixes of metric units correlate to place values in the base-10 number system. The table shows how metric units are based on powers of 10.

You can convert units within the metric system by multiplying or dividing by powers of 10. To convert to a smaller unit, you must multiply. To convert to a larger unit, you must divide.

Write this at the bottom of page 103.

Holt CA Course 1

4-9 Metric Measurements

Move the decimal point 2 places left: 5.30.

Convert the measure.

530 cL to liters

530 cL = (530 ÷ 100) L100 cL = 1L, so divide by 100.

= 5.3 L

Example 2A: Converting Metric Units

Holt CA Course 1

4-9 Metric Measurements

Example 2B: Converting Metric Units

1,070 g = (1,070 1,000) mg1 g = 1000 mg, so multiply by 1000.

= 1,070,000 mgMove the decimal point 3 places right: 1,070.000.

Convert the measure.

1,070 g to milligrams

Holt CA Course 1

4-9 Metric Measurements

Eliza buys one pumpkin that has a mass of 3 kg and another that that has a mass of 2,150 g. Which pumpkin has the greater mass? Use estimation to explain why your answer makes sense.Convert 2,150 g to kilograms.

1,000 g = 1 kg, so divide by 1,000.2,150 g = (2,150 ÷ 1,000) kg

Move the decimal point 3 places to the left.

= 2.150 kg

3 kg > 2 kg, so the answer makes sense.

Example 3: Using Unit Conversion to Make Comparisons

The 3 kg pumpkin has the greater mass.

2,150 g is about 2,000 g or 2 kg

Check Round 2,150 to the nearest thousand.

Holt CA Course 1

4-9 Metric Measurements

Choose the most appropriate metric unit for the measurement. Justify your answer.

The amount of liquid in 10 teardrops

Check It Out! Example 1

Milliliters—The amount of liquid in 10 teardrops is similar to the amount of liquid in several eyedroppers.

Holt CA Course 1

4-9 Metric Measurements

Check It Out! Example 2

580 g = (580 100) cg1 g = 100 cg, so multiply by 100.

= 58,000 cgMove the decimal point 2 places right: 580.00.

Convert the measure.

580 g to centigrams

Holt CA Course 1

4-9 Metric MeasurementsCheck It Out! Example 3

Tyesha purchases a bag of potatoes that has a mass of 2.5 kg and Casey purchases a bag with a mass of 3,850 g. Which bag of potatoes has the greater mass?

You can convert the mass of Tyesha’s bag to grams.

1 kg = 1000 g, so multiply by 1,000.

2.5 kg = (2.5 1,000) g

Move the decimal point 3 places right: 2.500.

= 2,500 g

Tyesha’s 2,500 g bag of potatoes has a smaller mass.

Holt CA Course 1

4-9 Metric Measurements

Check It Out! Example 3 Continued

Tyesha purchases a bag of potatoes that has a mass of 2.5 kg and Casey purchases a bag with a mass of 3,850 g. Which bag of potatoes has the greater mass?

Check

3,850 g is about 4000 g or 4 kg. 4 kg > 2.5 kg, so the answer is reasonable.