## Casio calculator

The Casio fx-83ES calculator is currently on sale in WH Smiths, Sainsbury’s and other outlets as ‘the GCSE’ calculator. The machine has a shed load of features, and it brings the use of a ‘natural’ notation further in calculator input.

The calculator has different ‘IO modes’ so that the input and output can be configured. The calculator is in mathIO by default, so that 1 ÷ 3 gives the fraction a third as the answer, and 10 × √ 162 gives the answer 90√2 !

The work round is to press SHIFT MODE 2 to put the calculator in a decimal mode. This mode is called lineIO – I suppose the ‘line’ comes from the idea of decimal numbers on a single line. Shift-mode 3 also puts the calculator into Degrees mode (I have noticed a couple working in grads).

While I can understand the desire to show off the capabilities of this calculator, I do think that setting surd/fractions format as the *default* mode is a little off-putting for new users.