1)   Multipurpose Calculator - MultiplexCalc 5.4
MultiplexCalc is a multipurpose and comprehensive desktop calculator for Windows. It can be used as an enhanced elementary, scientific, financial or expression calculator.
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 2)   CalculatorX 1.2. 6688
CalculatorX is an enhanced expression calculator. It supports common operations, constants,built-in and custom functions, variables and note-lines. You can even use Binary, Octal, Decimal and HEXadecimal numbers in one expression to evaluate as well.
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 3)   Compact Calculator - CompactCalc 4.2
CompactCalc is an enhanced scientific calculator for Windows with an expression editor. It embodies prime numbers, rational numbers, generic floating-point routines, hyperbolic and transcendental routines.
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 4)   Multivariable Calculator - SimplexCalc 4.1
SimplexCalc is a multivariable desktop calculator for Windows. It is small and simple to use but with much power and versatility underneath. It can be used as an enhanced elementary, scientific, financial or expression calculator.
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