Top Drawer Teachers The Australian Association of Mathematics Teachers (AAMT) Inc. http://topdrawer.aamt.edu.au

1. Here are three
sets of 10.
How many sets of
5 are there?
Five times

2. There are two
sets of 5 in
each 10 so
there must be
six sets.
There are two
sets of 5 in
each 10 so
there must be
six sets.
Five times

3. So what is
6 x 5 ?
Five times

4. 3030
Five times

5. So what is
8 x 5 ?
Five times

6. 4040
Five times

7. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
There is a pattern
in the answers we
have found. What
do you notice?
Five times

8. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
Five times
I can see
doubling
and
halving.
I can see
doubling
and
halving.

9. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
Give me an
example.
Five times

10. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
Five times
4 is doubled
to get 8.
10 is halved
to get 5.
4 is doubled
to get 8.
10 is halved
to get 5.

11. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
What should go on
this card?
Five times

12. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
Five times
It should be
3½ x 10 = 7 x
5
It should be
3½ x 10 = 7 x
5

13. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
So what is 7 x 5?
Five times
3½ x 10 = 7 x 5

14. 2 x 10 = 4 x 5
3 x 10 = 6 x 5
4 x 10 = 8 x 5
5 x 10 = 10 x 5
Five times
3½ x 10 = 7 x 5
3535