Casio FX-991DE Scientific Calculator

The Casio FX-991DE Plus is an easy-to-use technical and scientific calculator with a large range of functions. The 'Natural display' lets you enter and display fractions, square roots and other numeric expressions in the same way as they appear in your textbook. The calculator is powered by a via solar cell and a back-up battery.

• Total of 580 functions
• Solar powered with battery backup
• Supplied complete with hard protective case
• Features include: repeat function, 24 bracket layers, variable memory (9), STO/RCL button, scientific functions and statistics
• Natural input for simple entry of fractions, roots, powers, brackets, amounts, numerical differentiation/integration, sums, non-natural input (such as the MS models), output in √ form and output in pi form
• Casio type FX991DE