Page 13 - 新思维数学学生用书5 样章

1 The number system

4 Write these numbers in words and digits.
a 200 000 + 6000 + 300 + 2 + 0.1

b 900 000 + 90 000 + 900 + 9 + 0.9
c 100 000 + 20 000 + 5000 + 600 + 20 + 5 + 0.4 + 0.03

Swap books with your partner and check their answers.

5 Write the missing numbers.

a 358 × 100 = b 2700 ÷ = 27

c 5600 ÷ 1000 = d 456 × 1000 =

6 Sofia multiplies a number by 10, then again by 10 and then again by 10.
Her answer is 20 000.

What number did she start with?
7 Write the missing numbers.

a 3.45 × 100 = b 16.8 ÷ 10 =

c 6.5 × 10 =

8 Find and correct the mistakes in this diagram.

58.0

× 10
5800 0.58

× 100 ÷ 100
58

÷ 10 × 1000

5.8 5800

9 Which missing number is the odd one out?

A 33 ÷ 10 = B × 100 = 330

C × 10 = 30.3 D 3300 ÷ 1000 =

Explain your answer.

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