How to set up the maximum volume spreadsheet

The length of the A4 sheet of paper is rounded up to 30cm; the width is 21cm.

Type in the column headings: Width, Length Height and Volume.

Enter a height in C2; in this example 1.

The width of the box is worked out from the height. The formula in A2 is 21-2*C2. This formula is filled down column A.

The length of the box is worked out from the height.

The formula in B2 is 30-2*C2. This formula is filled down column B.

The volume of the box is worked out from the width, length and height.

The formula in D2 is A2*B2*C2. Drag this down the column.

The formula in C3 is C2+0.1. Drag this formula down the column. The numbers in column C will go up in tenths. This can be changed later to C2+0.01 or even C2+0.00000001 in order to close in on the maximum volume. Pupils have been known to work to fifteen decimal places!

To draw the graph: highlight the columns C and D and then click on the chart wizard . Select the XY (Scatter) and follow the instructions to label the axes and give the graph a title.