## Topic outline

• ### Metric Measure of Length

• 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

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