Page 139 - ICSE Math 4

Example 1: Convert the following to cen metres: (a) 5 m and (b) 6 m 98 cm.
Solu on: (a) 5 m = 5 × 100 cm = 500 cm

(b) 6 m 98 cm = (6 × 100) cm + 98 cm = 600 cm + 98 cm = 698 cm

Centimetres to metres

When we convert cen metres to metres or cen metres to metres and cen metres, the
last two digits always stand for cen metres and the rest of the digits stand for metres.

Example 2: Convert the following to metres or metres and cen metres.
(a) 432 cm (b) 2,465 cm

Solu on: (a) 432 cm = 4 m 32 cm (b) 2,465 cm = 24 m 65 cm

Kilometres to metres

In the metric system, 1 km = 1,000 m.

 To convert kilometres to metres, we mul ply the number of kilometres by 1,000.
 To convert kilometres and metres to metres, we mul ply the number of kilometres
by 1,000 and then add the number of metres to it.

Example 3: Convert the following to metres. Top Tip

(a) 10 km (b) 5 km 308 m To convert km to m,

Solu on: (a) 10 km = 10 × 1,000 m = 10,000 m put three zeros to the
right of the number.
(b) 5 km 308 m = (5 × 1,000) m + 308 m

= 5,000 m + 308 m = 5,308 m

Metres to kilometres

When we convert metres to kilometres or kilometres and metres, the last three digits
stand for metres and the rest of the digits stand for kilometres.

Example 4: Convert the following to kilometres or kilometres and metres.

(a) 9,734 m (b) 84,765 m
Solu on: (a) 9,734 m = 9 km 734 m (b) 84,765 m = 84 km 765 m

Exercise 11.1

1. Name the unit you will use to measure the length of the following objects.

(a) Length of a book (b) Length of a saree

(c) Length of a dining table (d) Distance between Bombay and Goa
(e) Length of a swimming pool (f) Distance of a marathon race

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