### Let’s Think About It

Caleb is playing a math game on the computer. He has to compare metric units by filling in the blank with the correct sign. His choices are greater than (>), less than (<), or equal to (=). This is the problem Caleb is working on.

What should Caleb choose?

In this concept, you will learn to convert metric units of length, mass, or capacity.

### Guidance

This concept combines a couple of different skills. Here you will combine converting metric units of length, mass, and capacity and multiplying decimals using powers of ten.

Converting metric units using powers of ten involves moving the decimal point.

Use this chart as a guide.

Metri Unit |
kilo- |
hecto- |
deka- |
(base unit) meter/gram/liter |
deci- |
centi- |
milli- |

Symbol | k | h | da | m/g/L | d | c | m |

Number | 1,000 | 100 | 10 | 1 | 0.1 | 0.01 | 0.001 |

Here is a conversion problem.

When you convert a larger unit to a smaller unit, multiply the number by a power of ten. 1 centimeter is equal to 10 millimeter. You multiply by a power of ten once or . Therefore, multiply 150 cm by 10.

Move the decimal point one place to the right when multiplying by 10. The decimal point in a whole number is after the number. Add a zero placeholder to 150.

Let’s look at this one involving capacity.

When you convert a smaller unit to a larger unit, divide the number by a power of ten. 1,000 milliliters is equal to 1 liter. You divide by a power of ten 3 times or

. Divide 1250 milliliters by 1,000.

Move the decimal point three places to the left when dividing by 1,000.

You can convert any unit of measure as long as you know the conversion equivalents and remember how to use powers of ten to move the decimal point to the left or to the right.

### Guided Practice

Convert the units of measurement.

First, identify the unit conversion. You are converting a smaller unit to a larger unit so you will divide. You know that a milliliter is one-thousandth of a liter.

Then, divide 12,350 by a power of

or 1,000. Move the decimal point three places to the left.

12,350 milliliters is equal to 12.35 liters.

### Examples

Covert the units of measurement.

#### Example 1

First, identify the unit conversion. You are converting a smaller unit to a larger unit so you will divide.

Then, divide 1,340 mL by a power of

or 1,000. Move the decimal point three places to the left.

1,340 milliliters is equal to 1.34 liters.

#### Example 2

First, identify the unit conversion. You are converting a larger unit to a smaller unit so you will multiply.

Then, multiply 66 g by a power of

or 1,000. Move the decimal point three places to the right.

66 grams is equal to 0.066 milligrams.

#### Example 3

First, identify the unit conversion. You are converting a smaller unit to a larger unit so you will divide.

Then, divide 1,123 m by a power of

or 1,000. Move the decimal point three places to the left.

1,123 meters is equal to 1.123 kilometers.

### Follow Up

Remember Caleb’s math problem?

Caleb has to compare complete the math problem.

First, convert 5.5 g to mg. You are converting a larger unit to a smaller unit so you will multiply.

Then, multiply 5.5 by a power of

or 1,000. Move the decimal point three places to the right.

Next, substitute 5,500 mg for 5.5 g in the original problem and compare.

Caleb should answer that 5.5 g is greater than (>) 4,500 mg.

### Video Review

https://www.youtube.com/watch?v=w0nqd_HXHPQ

https://www.youtube.com/watch?v=cMFwpxkIFMY

### Explore More

Convert the units of measurement using powers of ten.

- 5.6 km = ______ m
- 890 m = ______ km
- 9230 m = ______ km
- 40 cm = ______ mm
- 5000 mm = ______ cm
- 500 cm = ______ m
- 7.9 m = ______ cm
- 99 m = ______ cm
- 460 cm = ______ m
- 34 cm = ______ m
- 4.3 km = ______ m
- 760 m = ______ km
- 4300 m = ______ km
- 5000 g = ______ kg
- 560 mL = ______ L
- 6210 mL = ______ L
- 8900 mL = ______ L
- 18. 7.5 L = ______ mL
- 19. 0.5 L = ______ mL

### Answers for Explore More Problems

To view the Explore More answers, open this PDF file and look for section 4.20.