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Hong Kong
Stage 1

Complete statements to make a target number up to 20

Lesson

Here we're going to look at how we can make numbers by adding or taking away. 

If we add two numbers together we are going to make a bigger number. 

If we start with a number and take away we are going to make a smaller number. 

Let's take a look at how we can make new numbers by adding or taking away.

 

Use the sliders below to try adding and taking away to make a new number!

Worked Examples

QUESTION 1

Which of the following makes $16$16?

There may be more than one correct answer.

  1. $8+8$8+8

    A

    $9+8$9+8

    B

    $9+9$9+9

    C

    $8+7$8+7

    D

QUESTION 2

Which of the following makes $6$6?

There may be more than one correct answer.

  1. $8-2$82

    A

    $13-10$1310

    B

    $12-6$126

    C

    $15-9$159

    D

QUESTION 3

Let’s play a game called target number. Here’s how it works. I give you a target number and starting number and you tell me what I need to get there.

For example, our target number is $20$20, and if I tell you the number $19$19 you would say $1$1, because $19+1=20$19+1=20.

Find the missing number below for our target number $20$20.

  1. $18+\editable{}=20$18+=20

  2. $13+\editable{}=20$13+=20

  3. $20+\editable{}=20$20+=20

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