The metric system of measurement is based on powers of ten. To understand the metric system, you should know the meaning of the prefixes to each base unit.

Prefixes

kilo = thousand

hecto = hundred

deka = ten

deci = tenth

centi = hundredth

milli = thousandth

Now, applying these prefixes to length, volume, and mass should be easier.

Length—meter

1 kilometer (km) = 1,000 meters (m)

1 hectometer (hm) = 100 meters

1 dekameter (dkm) = 10 meters

10 decimeters (dm) = 1 meter

100 centimeters (cm) = 1 meter

1,000 millimeters (mm) = 1 meter

Volume—liter

1,000 milliliters (ml, or mL) = 1 liter (l, or L)

1,000 liters = 1 kiloliter (kl, or kL)

Mass—gram

1,000 milligrams (mg) = 1 gram (g)

1,000 grams = 1 kilogram (kg)

1,000 kilograms = 1 metric ton (t)

Approximations

A meter is a little more than a yard.

A kilometer is about 0.6 mile.

A kilogram is about 2.2 pounds.

A liter is slightly more than a quart.