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E:\Working\Orange_Education\TouchPad_Maths_2\Open_Files\Maths_2_Chapter-09
\ 14-Nov-2025 Bharat Arora Proof-7 Reader’s Sign _______________________ Date __________

Measure the length of your desk at school using your handspan.

How many handspans long is it? Ask your friend to do the
same with his/her handspan.

Did you both get the same length? Most probably
not. You will get the same length only if both of

you have handspans of the same length.

To avoid such differences, we use fixed units of
measurement, such as centimetres and metres.

Centimetre

This is a centimetre. We write centimetre as cm.

Tips

We use the word
‘about’ to show that
the measurement is
not exact.
about 1 cm about 3 cm about 15 cm

We use a cm ruler to measure shorter lengths.

Using a centimetre ruler

Place the object alongside the ruler, with one end of the object at the zero
mark.

Take the reading of the ruler at the other end of the object. This gives the
length of the object. The length of the pencil shown above is 8 cm.

Metre

We cannot measure the length of a wall with the help of cm. So, we use
metres to measure longer lengths. In short, we write metre as m.

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Measurement