Page 18 - 新思维数学学生用书5 样章

1 The number system

Check your progress

1 What is the value of the digit 3 in these numbers?
a 6703.46 b 7021.83 c 606 456.35

2 Write these numbers in words and digits.
a 100 000 + 3000 + 500 + 7 + 0.9

b 600 000 + 60 000 + 600 + 6 + 0.06

3 a What number is ten times bigger than 0.03?
b What number is one hundred times smaller than 555?

4 Round these lengths to the nearest whole number.
a 5.1 m b 16.5 cm c 10.4 m d 10.7 cm

5 Look at these number cards.

A 450 000 B 45 000 C 4500 D 450

E 45 F 4.5 G 0.45

Write the letter of the card that is one hundredth of 45.

6 Write the missing numbers.

a ÷ 1000 = 20

b 543 × 1000 = × 10

7 What is the missing number?

100 × 10 = 10 000 ÷

8 Sofia, Arun, Marcus and Zara each think of a number.

Their numbers are 3.5, 0.35, 35 and 0.53.

Use these clues to find the number each is thinking of.
• Arun’s number is ten times smaller than Marcus’s number.

• Zara’s number is not ten times smaller than Sofia’s or Arun’s or

Marcus’s numbers.
• Sofia’s number is ten times smaller than Arun’s number.

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