Power of 9 – Mathematics
Perimeter, Area, Volume – Community Garden
The Community Garden is a great practical example of the use of perimeter, area and
volume. You may wish one day to build your own vegetable garden:
how much stuff would you need to buy?
how much would it cost to do this?
Complete the following tasks:
No-dig garden beds:
You will need to draw a diagram of the Community Garden area on a sheet of A4 paper. You
may wish to use Google Earth or Google Maps to help you. Locate the position of the
You will also need to measure the “no dig” garden beds – one person from your Challenge
Group may wish to do this on behalf of the group, and share the data. You will need to
measure three things – the length, width and height of the beds. Take what you feel is a fair
average figure for each garden bed. Use metres as your unit of measurement.
1a) What is the total perimeter of one garden bed?
1b) What is the total perimeter of all of the garden beds?
1c) Timber to use as a surround for these garden beds comes in 4.8 metre lengths, and
can be joined. (Don’t worry about the details of joining the timber; just assume that you
can use all of it). Each 4.8m length costs $24.50. How many lengths of timber would
you need to make a border for one garden bed?
1d) What would be the total cost for all of the garden beds?
1e) What is the volume of each garden bed in cubic metres, (m3)?
1f) What is the total volume of all of the garden beds?
Measure the internal length, width and height of the treated pine planter boxes. Use
centimetres as your unit of measurement.
How many planter boxes are there in total?
2a) What is the total volume of one planter box in cubic centimetres? (cm3)
2b) Given that there are 1000cm3 in one litre, how many litres in capacity is each
Each planter box contains layers of materials as follows:
A 7cm deep layer of straw, then
A 3cm deep layer of mushroom compost, then
One cup (250cm3) of chicken pellets, then (assume that this takes up no height)
Half a cup (125cm3) of crusher dust, (dolerite) (assume that this takes up no height).
3a) Each planter has three layers the above.
3b) Calculate the total volume of each material in each planter box.
3c) How many litres of each material is required for all of the planter boxes?
3d) How many percent full will each planter box be, assuming that none of the material
squashes/compresses in volume?