Page 14 - Length

4. Round off to the nearest 100:
(a) 78 cm (b) 145 cm (c) 991 mm
(d) 56 072 km (e) 301 mm (f) 23 450 km

5. Round off to the nearest 1 000:
(a) 1 991 mm (b) 6 072 km (c) 4 490 cm
(d) 2 500 m (e) 690 mm (f) 1 932 m

6. Mr Bengu is driving to Cofimvaba this weekend. The distance
is 543 km. How far is the distance to the nearest 100 km?

7. The route and distance of the Comrades Marathon between
Durban and Pietermaritzburg varies from year to year. In
2013, for example, the distance was 86 860 m. In 2015 the
organisers had to change the route because of roadworks and
it became 860 m longer than in 2013. What was the total
distance to the nearest 100 m in 2015?

4.7 Apply your skills

1. Arrange from the longest to the shortest:

(a) 1 000 mm; 900 cm; 2 m

(b) 39 m; 395 mm; one quarter of a km; 100 cm

(c) 125 cm; 248 mm; 2 km; 500 m
(d) 449 m; 944 cm; 4 944 mm

2. Mrs Tailor bought 5 m of material with a width of 2 m. She
wants to make serviettes. The serviettes are squares with side
length 23 cm. How many serviettes will she be able to make?
Allow 2 cm for seams around each serviette.

3. A skyscraper has 90 floors. Each floor is 3 m 50 cm high. About
how high is the building?

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