We use standard units to measure length. The standard unit for measuring length are **centimetre (cm)**, **metre (m)** and **kilometre (km)**. We use these measurements depending on how large or small the length or distance is. For measuring large distance we use kilometre and for measuring small distance we use metre and centimetre. This maths chapter – **Measurement of Length** is important for students studying in class 3. Lets begin.

Let’s see relation between **centimetre (cm)**, **metre (m)** and **kilometre (km)**.

1 metre = 100 centimetres OR 1 m = 100 cm

1 kilometre = 1000 metres OR 1 km = 1000 m

### Conversion of length

**Let’s learn how to convert metres (m) into centimetres (cm).**

We know that 1 m = 100 cm.

(1) To convert metres into centimetres, multiply the metres by 100.

(2) To convert metres and centimetres into centimetres, multiply metres by 100 and add the centimetres.

### Examples

**Convert 15 metres into centimetres.**

1 m = 100 cm

Therefore, 15 m = 15 x 100 cm = 1500 cm

15 m = 1500 cm.

**Convert 15 metres 25 centimetres into centimetres.**

Again, 1 m = 100 cm

Therefore, 15 m = 15 x 100 cm = 1500 cm

15 m = 1500 cm

Therefore, 15 m 25 cm = 1500 cm + 25 cm = 1525 cm.

### Exercise 1: Convert into centimetres.

- 10 m

10 m = 10 x 100 cm = 1000 cm

So, 10 m = 1000 cm - 25 m

25 m = 25 x 100 cm = 2500 cm

So, 25 m = 2500 cm - 63 m

63 m = 63 x 100 cm = 6300 cm

So, 63 m = 6300 cm - 110 m

110 m = 110 x 100 cm = 11000 cm

So, 110 m = 11000 cm

### Exercise 2: Convert into centimetres.

- 4 m 25 cm

4 m = 4 x 100 cm = 400 cm

So, 4 m 25 cm = 400 cm + 25 cm = 425 cm - 11 m 75 cm

11 m = 11 x 100 cm = 1100 cm

So, 11 m 75 cm = 1100 cm + 75 cm = 1175 cm - 25 m 33 cm

25 m = 25 x 100 cm = 2500 cm

So, 25 m 33 cm = 2500 cm + 33 cm = 2533 cm - 73 m 49 cm

73 m = 73 x 100 cm = 7300 cm

So, 73 m 49 cm = 7300 cm + 49 cm = 7349 cm

**Let’s learn how to convert centimetres** **(cm) into metres (m).**

We know that 100 cm = 1 m.

To convert centimetres into metres, divide the centimetres by 100.

The quotient is the metres and the remainder gives the centimetres.

### Examples

- Convert 500 cm into m.

Divide 500 by 100,

500 cm ÷ 100 = 5

Quotient = 5, Remainder = 0

So, 500 cm = 5 m - Convert 5275 cm into m.

On dividing 5275 by 100, we get

Quotient = 52, Remainder = 75

So, 5275 cm = 52 m 75 cmOther method:

5275 cm = 5200 cm + 75 cm

We know that 5200 cm = 52 m

So, 5275 cm = 52 m + 75 cm = 52 m 75 cm

### Exercise 3: Convert into metres.

- 500 cm

On dividing 500 by 100,

Quotient = 5 and Remainder = 0

So, 500 cm = 5 m - 1200 cm

On dividing 1200 by 100

Quotient = 12 and Remainder = 0

So, 1200 cm = 12 m - 5400 cm

On dividing 5400 by 100

Quotient = 54 and Remainder = 0

So, 5400 cm = 54 m - 9000 cm

On dividing 9000 by 100

Quotient = 90 and Remainder = 0

So, 9000 cm = 90 m

### Exercise 4: Convert into metres.

- 5675 cm

5675 cm = 5600 cm + 75 cm

5600 cm = 56 m

So, 5675 cm = 56 m + 75 cm = 56 m 75 cm - 7009 cm

7009 cm = 7000 cm + 9 cm

7000 cm = 70 m

So, 7009 cm = 70 m + 9 cm = 70 m 9 cm - 8806 cm

8806 cm = 8800 cm + 6 cm

8800 cm = 88 m

So, 8806 cm = 88 m + 6 cm = 88 m 6 cm - 9060 cm

9060 cm = 9000 cm + 60 cm

9000 cm = 90 m

So, 9060 cm = 90 m + 60 cm = 90 m 60 cm

**Now, let’s learn how to convert kilometres (km) into metres (m).**

We know that 1 kilometre (km) = 1000 metre (m).

(1) To convert kilometres into metres, multiply the kilometres by 1000.

(2) To convert kilometres and metres into metres, multiply kilometres by 1000 and add the metres.

### Examples

**Convert 15 km into m.**1 km = 1000 m

So, 15 km = 15 x 1000 m = 15000 m

**Convert 9 km 500 m into m.**9 km = 9 x 1000 m = 9000 m

So, 9 km 500 m = 9000 m + 500 m = 9500 m

### Exercise 5: Convert into metres.

- 10 km

10 m = 10 x 1000 m = 10000 m

So, 10 km = 10000 m - 5 km

5 km = 5 x 1000 m = 5000 m

So, 5 km = 5000 m - 37 km

37 km = 37 x 1000 m = 37000 m

So, 37 km = 37000 m - 95 km

95 km = 95 x 1000 m = 95000 m

So, 95 km = 95000 m

### Exercise 6: Convert into metres.

- 4 km 250 m

4 km = 4 x 1000 m = 4000 m

So, 4 km 250 m = 4000 m + 250 m = 4250 m - 7 km 75 m

7 km = 7 x 1000 m = 7000 m

So, 7 km 75 m = 7000 m + 75 m = 7075 m - 10 km 1 m

10 km = 10 x 1000 m = 10000 m

So, 10 km 1 m = 10000 m + 1 m = 10001 m - 15 km 100 m

15 km = 15 x 1000 m = 15000 m

So, 15 km 100 m = 15000 m + 100 m = 15100 m

**Let’s learn how to convert metres (m) into kilometres (km).**

We know that 1000 m = 1 km.

To convert metres into kilometres, divide the metres by 1000.

The quotient is the kilometres and the remainder gives the metres.

### Examples

- Convert 6000 m into km.

Divide 6000 by 1000,

6500 cm ÷ 1000 = 6

Quotient = 6, Remainder = 0

So, 6000 m = 6 km - Convert 7275 m into km.

On dividing 7275 by 1000, we get

Quotient = 7, Remainder = 275

So, 7275 m = 7 km 75 mOther method:

7275 m = 7000 m + 275 m

We know that 7000 m = 7 km

So, 7275 cm = 7 km + 275 m = 7 km 275 m

### Exercise 7: Convert into kilometres.

- 5000 m

On dividing 5000 by 1000,

Quotient = 5 and Remainder = 0

So, 5000 m = 5 km - 12000 m

On dividing 12000 by 1000

Quotient = 12 and Remainder = 0

So, 12000 m = 12 km

### Exercise 8: Convert into metres.

- 1200 m

On dividing 1200 by 1000

Quotient = 1 and Remainder = 200

So, 1200 m = 1 km 200 m - 3005 m

On dividing 3005 by 1000

Quotient = 3 and Remainder = 5

So, 3005 m = 3 km 5 m - 6470 m

On dividing 6470 by 1000

Quotient = 6 and Remainder = 470

So, 6470 m = 6 km 470 m - 9509 m

On dividing 9509 by 1000

Quotient = 9 and Remainder = 509

So, 9509 cm = 9 km 509 m

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