MEASUREMENT • WORKING OUT AREA WITH A FORMULA MEASUREMENT • WORKING OUT AREA WITH A FORMULA
Working out area
with a formula
Using a formula is a much easier way to find a shape’s area
than having to count squares. Calculating with a formula means
you can find the area of large shapes more quickly.
The area of a square
or rectangle is:
length × width
TRY IT OUT
See for yourself
The sandpit in the playground is 4 m long and 2 m wide.
Can you use the formula to find the area of the sandpit?
If we put a square grid over the playground,
we would see eight rows of six 1 m² units,
making a total area of 48 m².
There is a quicker way to find the
area than counting squares. We can
use a formula.
If we multiply 6 by 8, we get 48. This is the
same number as the number of metre
squares we can fit into the playground.
We can write this as a formula that will work
for any rectangle, including squares:
Area = length × width
Look at this playground. We know that it has
a width of 6 m and a length of 8 m.
4 m
2 m
WIDTH
6 m
LENGTH
8 m
Answer on page 319
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