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Narrator: Large print and talking calculators are an example of how everyday tools are being made accessible to people who are blind or visually impaired and assisting them in the classroom, at work, and at home.

The two devices shown here look like standard desktop calculators, but they both provide speech output. One of them also shows enlarged numerals on its LCD display.

While some people with low vision prefer to use talking calculators, others may choose to use a calculator with an enlarged display. The size of the numerals displayed varies from device to device. Users need to make sure that they select a model on which the display is large enough for them to read comfortably.

This unit performs all the usual calculator functions, but it speaks each number that the user enter. This audio capability also allows users to hear the results of calculations that would just be displayed on a standard calculator.

Sample of calculator's speech: "78 plus 51, equals 129"

This calculator is similar to the previous device in that it speaks a numeral each time the user presses a key and then reads the results as they appear on the screen. In addition to performing standard functions, this device allows the user to perform scientific calculations using algebra, trigonometry, or calculus. It will also convert between various numerical systems.

Devices such as these allow people who are blind or visually impaired to work along side sighted colleagues performing complex mathematical problems.

They range in price from $25 for a simple four function calculator, to around $200 for a talking scientific model, and around $600 for a specific business or statistical calculator.