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Ordering Cards

Look at these cards.

7

×2

3

×6

12

÷3

14

−2

4

×2

20

+1

10

×2

5

×2

8

−5

15

÷3

21

÷3

18

−3

Can you sort them so that they follow round in a loop?
 
Here is a card from a different set.

10

×3

What number would follow it?
 
What about this one? What would follow it?

12

÷2

What calculation might be on the card before this one?

You might like to print off and cut out the first set of cards.

Why do this problem?

This problem is designed to help children to learn, and to use, the two and three times tables.

Possible approach

You could print out the sheet of cards and cut it into the twelve separate cards and give the individual cards to the group to work on in pairs, so that they are able to talk through their ideas with a partner.

The cards should form a loop so it does not matter which card is used to start. If you want to make the loop longer, or make your own loop, you could download these similar blank cards.
 
If you lengthen the loop you will need to take out one card and replace it with your new ones. Try to avoid repeating a number which has been used already, and avoid multiplying and then immediately dividing by the same number.

Key questions

Which card did you start with?
How does your sequence of numbers go?
Look carefully at the loop here and check your answers.

Possible extension

Learners could make their own set of looping cards using the blank cards.

Possible support

Some children might benefit from having a written version of the two and three times tables to help them, or using a calculator.