In THIS CASE, We Are Talking Only About LENGTH , So the Base Unit Is the METER

Name: ______Block: ____ Date: ______

Measuring Metric Length: BACKGROUND: THE BASICS @ USING A “METER STICK” Remember Metric “base units” and “prefixes”…? Base units are known/set sizes for length (meter), volume (liter), mass (gram), etc. Prefixes are added to base units to make larger and smaller units of measurement. (ALSO, in Metrics, ALL UNITS are divided into 10 equal parts, so decimals can be used to describe fractions of a unit. That’s HUGE!)

BASE UNITS: In THIS CASE, we are talking only about “LENGTH”, so the base unit is the METER.

PREFIXES: There are two types of prefixes, those that make smaller units and those that make larger units.

Prefix Fraction Prefix Multiple

deci- 1/10th = .1 deca- 10 base units centi- 1/100th = .01 hecto- 100 base units milli- 1/1000th = .001 kilo- 1,000 base units

Examples: 1 decimeter = 1/10th of a meter (.1m) 1 hectometer = 10 meters (10m)

THE METER STICK = 1 meter (close to actual size)

1 dm (decimeter)

QUESTIONS (Part I) - Look at the diagram: 1. How many millimeters (mm) are there in 1 centimeter (cm)? ______2. How many cm are there in 1 decimeter (dm)? ______3. How many dm are there in 1 meter (m)? (Study above and think!) ______4. How many cm are in a m? (Tough? Look again and think “fraction”.) ______5. If a “palm width” is about 10 centimeters, how many decimeters is it? ______dm 6. If a “pinkie width” is about 10 mm, how many centimeters is it? ______cm Name: ______Block: ____ Date: ______7. If a “dime width” is about 1/10th of a centimeter, how many mm is it? _____mm

PART II: Measuring to the “nearest unit”. In science, this year and in the future, you will be asked to make measurements in Metrics to the “nearest blank unit”. (This could be to the nearest “whole unit” or to some “fraction” of a unit, such as “tenth of” or “hundredth of” or any fraction of….)

Let’s practice it a little.

I------(Line A) I------(Line B) I------(Line C) I------(Line D)

Use the ruler above to measure Lines A-C according to the instructions below.

Example 1. Measure Line A to the nearest WHOLE centimeter: 6 cm _ (only whole units) 2. Measure Line A to the nearest TENTH of a centimeter: 6.0 cm (1 decimal place) 3. Measure Line A to the nearest HALF centimeter: 6.0 cm (only .0 or .5) 4. Measure Line D to the nearest HALF centimeter: 6.5 cm (only .0 or .5)

Problems 1. Measure Line B to the nearest WHOLE centimeter: ______

2. Measure Line B to the nearest TENTH of a centimeter: ______

3. Measure Line B to the nearest HALF centimeter: ______

4. Measure Line C to the nearest WHOLE centimeter: ______

5. Measure Line C to the nearest TENTH of a centimeter: ______

6. Measure Line C to the nearest HALF centimeter: ______Name: ______Block: ____ Date: ______Part III: Converting … Wait! DON’T PANIC! (Read ahead) First, Study your answers to the first four questions (just above). Then, look at the questions below and “calculate” the answer. (Study the picture again, if you need to.) You can DO-eeeeeeeet! (Frenchie, from “Waterboy”) Example 1. How many millimeters (mm) are in a decimeter (dm)? ______(There are 10 mm in 1 cm and 10 cm in 1 dm, so, ten tens, or 10 x 10 = ___ mm/dm.)

Another way to see this is using the “Factor-Label” method: 10 mm x 10 cm = 10 mm x 10 cm = 100 mm 1 cm 1 dm 1 cm x 1 dm 1 dm Example 2. How many millimeters (mm) are in a meter (m)? ______i. Start with the units you want to find in the numerator; write the # of those units, per the next size unit, in the numerator: - here, 10 millimeters in 1 cm (10 mm/ 1 cm). ii. Finish with the units you want in the denominator: - here, meters (10 dm/ 1m). iii. In between, continue with all of the unit fractions in between: - here, 10 cm/1 dm)

Then, write the math equation and cancel the units which match. 10 mm * 10 cm * 10 dm = 10 mm x 10 cm x 10 dm = 1,000 mm 1 cm 1 dm 1 m 1 cm x 1 dm x 1 m m Problem 1. How many meters are in 1.5 kilometers?

10 km * 10 cm * 10 dm = 10 mm x 10 cm x 10 dm = 1,000 mm 1 cm 1 dm 1 m 1 cm x 1 dm x 1 m m

THE METER STICK = 1 meter

1 dm (decimeter)