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Why the metric system?

• decimal systems based on 10 (easy math!!)

• used in most of the world – cars, factories, building construction

• used everywhere by scientists (can’t use anything else in science!!)

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Liberia

Myanmar

In the metric and SI systems, one unit is used for each type of measurement:

Measurement Metric common

Length meter (m) distanceVolume liter (L) liquidsMass gram (g) weightTime second (s)Temperature Celsius (C) (Fahrenheit)

Kelvin (K)

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• makes units larger or smaller• Pneumonic device!!!king henry died by drinking choc.

milk

k h da base d c m

Kilo hecto deka (base unit) deci cent milli

GRAM – g

LITER – L

METER - m Note: if the m is first it is milli Note: if the m is second it is meter

mL = milliLiter dm = decimeter

Mass of paperclip = 1 gram Width of jumpdrive = 1 centimeter Large pop bottle = 2 Liters Width of wire of paperclip = 1 millimeter Nickel = 5 grams Penny = 2.5 grams Doorknob height = 1 meter CD diameter = 12 centimeter

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What unit would you use to measure

A. your height?

B. your mass?

C. the distance between two cities?

D. the width of an artery?

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An equality• states the same measurement in two different

units• can be written using the relationships between

two metric units

Example: 1 meter is the same length as 100 cm and 1000

mm. 1 m = 100 cm

1 km = 1000 m1 in = 2.54 cm (English to

Metric)8

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1 mL = 1 cm3

• Several equalities can be written for mass in the metric (SI) system.

Example: 1 gram is the same

mass as 1000 mg and 0.001 kg. 1 kg = 1000 g 1 g = 1000 mg 1 kg = 2.2 lbs (metric to English)

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How many Liters are equal to 1357 mL?How many kilograms are equal to 345 cg?0.25 kg is equal to how many grams?How many mL are equal to 2.78 L?147 mL is equal to how many Liters?How many mg are equal to 0.275 kg?

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How many Liters are equal to 1357 mL?1.357 L

How many kilograms are equal to 345 cg?0.00345 kg

0.25 kg is equal to how many grams?250 g

How many mL are equal to 2.78 L?2780 mL

147 mL is equal to how many Liters?0.147 L

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