1. The SI System of Measurement. and How to measure LENGTH.

2. The Metric system Developed in the late 1700’s Based on multiples of 10 First adopted by the French in 1793 Adopted by the US Congress in 1866

3. SI System SI = “Systeme International d’Unites” It is an improved version of the Metric System. Adopted by the US Congress in 1960. It is the standard system of measurement WORLDWIDE!

4. Base Units Length = meter Mass = gram (standard is a Kilogram) Volume = liter Time = second Temperature = Kelvin Electric Current = Ampere Quantity of Matter = Mole

5. Prefixes (m + Base Unit)milli = 1/1000 (m + Base Unit) (c + Base Unit)centi = 1/100 (c + Base Unit) (d + Base Unit)deci = 1/10 (d + Base Unit) (da + Base Unit)Deka = 10 (da + Base Unit) (h + Base Unit)Hecto = 100 (h + Base Unit) (k + Base Unit)Kilo = 1000 (k + Base Unit)

6. How to measure Length Think by 10’sThink by 10’s = –10 millimeters (mm) = 1 centimeter (cm) = –10 cm = 1 decimeter (dm) = –10 dm = 1 meter (m) = –10 m = 1 Dekameter (dam) = –10 dak = 1 Hectometer (hm) = –10 hm = 1 Kilometer (km)

7. Every Space is divided into 10 equal parts –One meter is equal to 10 decimeters –One decimeter is equal to 10 centimeters –One centimeter is equal to 10 millimeters –One millimeter is also divided into 10 sections even though they are not drawn on a meter stick. (This is your Best Guess Number) How to measure Length

8. Example 01234centimeters millimeters How many cm? 4.00 cm # of cm after Zero# of mm after 4cm Best Guess Number from 1-10 after mm How many mm? 40.0 mm

9. Example 01234 How many cm? 2.40 cm How many mm? 24.0 mm

10. Example 7475767778 How many cm? 75.45 cm How many mm? 754.5 mm

11. Example How many cm? 0.23 cm How many mm? 2.3 mm 0 5

12. 0 5 Example How many cm? 3.05 cm How many mm? 30.5 mm