# The Classwiz calculator: comparing with Casio 991ES

In the next school year we will be asking all A level maths and further maths students to buy the new Casio Classwiz calculator. The new syllabuses require functions available only on this and other similar calculators. It costs about £30 on Amazon, but the school should be able to get a bulk buy at around £20. You can, as of now anyway, get a Classwiz calculator yourself, in advance, at a similar price on eBay.

If you already have a Casio 991ES, previously the most advanced Casio scientific calculator, then as of now (and this may change as more students switch to the Classwiz) you can get a reasonable price by selling it on eBay.

Review of the Classwiz by Abdal Mohammad (thanks to Abdal for this)

• The display is much better. If you want to convert a complex number to polar form, for example, you get the answer clearly on the screen in surd and fraction-of-π form if appropriate, rather than having to scroll across to see the r and then the θ, and having to use the Alpha>X and Alpha>Y key combinations to get them in surd and fraction-of-π form.
• It solves cubics and quartics neatly, including giving complex roots.
• It solves polynomial inequalities neatly (useful for FP2).
• It does matrix calculations more neatly and clearly than the 991ES.
• It find cross-product of vectors, which the 991ES doesn’t, and does many other vector calculations.
• It evaluates sums of series between given numerical bounds.
• The OPTN key provides a menu of further options that are relevant to a particular mode. It gives access to hyperbolic functions, to symbols for different angle measures, and the various engineering symbols.
• Twelve calculator modes are available by tapping on the MENU button. Each mode has an image that better visualises what each mode works to do and what it is.
• Calculations in statistics (e.g. the normal distribution) are smoother and more intuitive.
• It can handle simultaneous equations with up to four unknowns, and deal with quadratics, cubics, quartics, and even quintics, stating the turning point for each.
• It has a QR code generation which you can scan with your iPhone, which makes it a cheap alternative to a graphics calculator if you want to visualise graphs.

Additional comment from me about the Classwiz and statistics:

The new spec for ordinary A level maths says:

“Use of a calculator to find individual or cumulative binomial probabilities”

“Students will be expected to use their calculator to find
probabilities connected with the normal distribution.”

It is not really clear what this means, because the Edexcel formula book still has a table of binomial probabilities (and a few, but only a few, values for the normal distribution); but that’s what the spec says.

On the Classwiz, finding those probabilities is intuitive and easy.

On the 991es, you can find the normal cdf from a z-value. But you have to calculate the z, whereas on the Classwiz you can input x, μ, σ, and get your answer straight from those.

On the 991es, you can calculate binomial probabilities, but only via the nCr function. As far as I can see, you can calculate the binomial cdf only by adding up.