Transcript Powerful numbers

Powerful Numbers
I am learning to solve multiplication problems with powers (exponents).
e.g. 22 or 23
The square below is 4
cubes high and 4 cubes
wide.
The square below is 2
cubes high and 2 cubes
wide.
The square below is 3
cubes high and 3 cubes
wide.
We can work out how
many cubes there are by
working out 2 X 2 = 4
We can work out how
many cubes there are by
working out 3 X 3 = 9
Using exponents we can
record this as 22
Using exponents we can
Using exponents we can
record this as 32
record this as 42
If I square root the 4.
If I square root the 9.
4
I get 2. This is the
length of the sides.
9
I get 3. This is the
length of the sides.
We can work out how
many cubes there are by
working out 4 X 4 = 16
If I square root the 16.
16
I get 2. This is the
length of the sides.
33 Can be represented
by a cube that is 3 small
cubes high, wide and
deep.
We can work out how many
small cubes were used to
make these by calculating 33
33 = 3 X 3 X 3
3X3=9
9 X 3 = 27
43 Can be represented
by a cube that is 4 small
cubes high, wide and
deep.
We can work out how many
small cubes were used to
make these by calculating 43
43 = 4 X 4 X 4
4 X 4 = 16
16 X 4 = 64
Numbers can be raised to powers of 4, 5, 6 etc.
These numbers get big very quickly. Lets look at a couple of examples.
Try to work these out as we go.
22
2X2= 4
23
2X2X2= 8
24
2 X 2 X 2 X 2 = 16
25
2 X 2 X 2 X 2 X 2 = 32
26
2 X 2 X 2 X 2 X 2 X 2 = 64
Work out answers to the questions below.
1) 33
27
2) 22
4
3) 24
16
4) 34
81
5) 27
Click again when you have worked out
all your answers.
128
Need some more practise? Try Pg47 & 48 of Teacher Tools Multiplication
and Division Book Numeracy resources