Page 13 - 新思维数学学生用书3 样章

1 Numbers to 1000

Worked example 1

What is the value of the ringed digit in this 3-digit number?

4 7 2

472 is four hundred and It helps to say the number
seventy-two. out loud.

The 7 is in the tens place. You say the value of each

The value of the 7 is 7 tens, digit as you read it.

so it is 70.

5 What is the value of the ringed digit in each 3-digit number?

6 3 7 10 9

9 21 3 9 4

76 8 2 53

Which tens values have not been used in these numbers?

Is it easier to find the value of the hundreds, tens or ones digit?

Why do you think that is?

Think like a mathematician

Tomas makes nine 3-digit numbers using a set of place value cards.

Seven of the numbers are 473, 689, 358, 134, 925, 247 and 791.

What could the other two numbers be?
Compare your numbers with those of someone else in your class.

If your numbers are different, can you explain why?

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