Page 130 - New Medley 5 Semester 2

Measurements

We are already familiar with the units of measurements. We have learnt in
the previous classes that unit of a measure like length, weight or capacity

is a fixed measure. When we say the measure (e.g., length) of something,
we compare it with its standard unit and say how many times the unit it is.

Examples: (a) Length of a matchstick is 5 cm. That means, it is 5 times
a cm.

(b) Capacity of a milk bottle is 200 mL. That means, the volume
it contains is 200 times a mL.

(c) Mass of bag is 5 kg. That means, it weighs 5 times a kg.

Note that a measurement is made up of a number and a unit.

5 cm

200 mL

5 kg

Number unit

Metric Measures (System)

We have learnt the units of Length, Mass and Capacity used in everyday
life. These units belong to a system called metric system. When we express

the measures using these units, they are called metric measures.

The metric system is a decimal system which uses multiples of ten for
converting various units into the system.

We know that length, mass and capacity are respectively measured in
metres, grams and litres. Different prefixes are used with these units in

the metric system. The most common prefixes are kilo, hecto- and deca-
for the bigger units and deci-, centi- and milli- for the smaller units.

Let us see the relationship among different units of the system under the
place-value chart.

128