UNIT ANALYSIS

property                                               metric unit                   abbreviation                

length                                                   meter                            m

volume                                                 liter                               L

mass                                                     gram                              g

temperature                                          degrees Celsius            °C

  prefix                                                    value                            abbreviation

  micro                                              1/ 1,000,000                              m

milli                                                      1/1,000                                  m

centi                                                     1/100                                     c

kilo                                              1000                                     k

Conversions of English to metric units

2.54 centimeter =  inch                                      1 liter = .95 quarts

1 pound = .45 kg

RATES:  ratios that compare quantities

Example:             2.2   is a ratio                              2.2 lb      is a rate

                           1                                                 1 kg

The number of centimeters in an inch can be written as a rate.

 Example:        2.54 cm                     If the rate is inverted ,     1in         , it is still true.

                        1 in                                                               2.54 cm

To use unit analysis multiply the quantity you are converting times the rate that relate to the unit you are converting to.

Example:    How many centimeters is 36 inches?       36 in  _X    2.54 cm    ₌  91.44 cm

                                                                                                   1 in

Notice that the rate is written so that the units cancel, leaving the unit you are asked to find.

Sometimes more than one rate is required.

Example:  How many inches is 25 mm?            25 mm  _X  1 cm   _X   2.54 in   ₌  6.35 in

                                                                                        10 mm         1 cm

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