Tallies are used to record quantities of particular items or products.

For instance, if you wanted to write down how many power tools you had taken onto a jobsite, your tally might read:

1 x jigsaw; 1 x circular saw; 3 x cordless drills; 2 x claw hammers ...

and so on.

But if you had a product that was already expressed in terms of its cross-section size, such as 70 x 19 skirting board, it would get very confusing if you started to use the 'x' ('times') sign to also indicate the number and length of the pieces.

Set out below are some examples of how to record tallies when you're working with items that are referred to by their cross sectional dimensions.

Example 1: skirting boards

Let's say you have 15 pieces of skirting board, 70 mm x 19 mm in size.

We'll say that 5 pieces are 2.4 metres in length, 7 pieces are 2.7 metres and 3 pieces are 3.6 metres.

To show this as a tally, you would write it as follows:

        70 x 19 skirting: 5/2.4, 7/2.7, 3/3.6

Now let's say we wanted to know how many lineal metres this tally represents.
Note that 'lineal' means 'in a line' - so to put the question another way: What is the total metreage of these pieces if they were all laid out in a line?

The easiest way to find the answer is to use a calculator with a memory button. Although not all calculators work in exactly the same way, the sequence of numbers and function buttons would be similar to that shown in the image.

To see this process written out in more detail, click on the link below.

Detailed description of calculation

If you don't have a calculator with a memory button, you can simply multiply each line separately and then add the subtotals together, as shown in this image.

Example 2: plywood sheets

Sheet materials sometimes have their dimensions shown in metres and sometimes in millimetres.

For example, if you had two sheets of ply that were 9 mm thick, 2.4 metres long and 1.2 metres wide, it could be written up as follows:

        9 mm ply: 2 / 2.4 x 1.2

or alternatively:

        9 mm ply: 2 / 2400 x 1200