Metric Measure of Length
Measurement of something from its one end to the other is called its length. The standard unit of length is meter. We use different units to measure different lengths. Millimeter, centimeter , decimeter are smaller unit used to measure smaller distance, meter is used to measure average distance, whereas units like decameter, hectometer and kilometer are used to measure longer distance. All these units are related to each other.
Changing Metric Units of Length
When we move from one metric unit to another to the right in the above metric chart, the value of metric unit becomes ten times smaller i.e. one tenth and when we move from one metric unit to another to the left in the metric chart, the value of metric unit becomes ten times bigger.
We consider meter as the basic unit of length.
1 Decameter (dam) = 10 times meter
1 Hectometer (hm) = 100 times meter
1 Kilometer (km) = 1000 times meter
1 Decimeter (dm) = 1/10 of meter
1 centimeter (cm) = 1/100 of meter
1 millimeter (mm) = 1/1000 of meter
Conversion of measures from higher to lower units
We always multiply when we change higher unit to lower unit.
Example 1: Change 4km into meters
1km =1000m
Therefore, 4 x 1000m = 4000m
Example 2: Change 25m into centimeters
1m = 100cm
Therefore, 25 x 100cm = 2500cm
Conversion of measures from lower to higher units
We always divide when we change lower unit to higher unit.
Example 1: Change 6000m to kilometer
1000m = 1km
Therefore, 6000 ÷ 1000 = 6km
Addition and Subtraction
Step1: Write the units on the top.
Step2: Write the numbers in proper place below the units. Write zero in empty place.
Example 1: Add 45km 34m and 34km 5m
Example 2: Subtract
15km 30m from 35km 45m
Multiplication involving units of measurement
Example 1: Multiply 23 m 60cm by 5
Division involving units of measurement
Example 1: Divide 484m 60cm by 4