Page 20 - 新思维数学活动用书3 样章

1.3 Estimating and rounding

Challenge

8 Round the height of each tower to the nearest 10 metres
and to the nearest 100 metres.

Height in Nearest Nearest
Name of tower Location
metres 10 metres 100 metres

Lakhta Centre St Petersburg 462

Willis Tower Chicago 442

Burj Khalifa Dubai 828

Kuala
Petronas Tower 1 452
Lumpur

Shanghai Tower Shanghai 632

Canton Tower Guangzhou 600

9 Which towers round to the same height when their heights are

rounded to the nearest 100 metres?

10 Zara rounds a number to the nearest 10 and to the
nearest 100. Her answer both times is 500.

What could her number be? Record all the possible answers.

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