METRIC SYSTEM UNITS OF LENGTH
ÞTo convert units of length in the metric system of measurement
The basic unit of length in the metric system is the meter. All units of length in the metric system are derived
from the meter. The prefix “centi-“means one hundredth.
1 centimeter=1 one-hundredth of a meter
kilo- = 1000 1 kilometer (km) =1000 meters (m)
hecto- = 100 1 hectometer (hm) = 100 m
deca- =10 1 decameter (dam) = 10 m
1 meter (m) = 1 m
deci- = 0.1 1 decimeter (dm) = 0.1 m
centi- = 0.01 1 centimeter (cm) = 0.01 m
milli- = 0.001 1 millimeter (mm) = 0.001 m
Conversion between units of length in the metric system involves moving the decimal point to the right or to
the left. Listing the units in order from largest to smallest will indicate how many places to move the decimal
point and in which direction.
Example 1: To convert 4200 cm to meters, write the units in order from largest to smallest.
km hm dam mdm cm mm Converting cm t o m requires moving
42 .0 0 2 positions to the left.
Move the decimal point the same number of places
and in the same direction (to the left).
So 4200 cm =42.00 m
A metric measuremen t involving two units is customarily written in terms of one unit. Convert the smaller unit
to the larger unit and then add.
Example 2: To convert 8 km 32 m to kilometers
First convert 32 m to kilometers.
km hm dam mdm cm mm
Converting m to km requires mo ving
0 . 0 3 2
2 positions to the left.
32 = 0 .0 32 km Move the decimal point the same number of places
and in the same direction.
So 8 km 32 m = 8 km +0.03 2 km
Add the result to 8 km
=8.03 2 km
Math 0300
Student Learning Assistance Center - San Antonio College
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