Tax+

[0]~ [9] [00]		:Numeral keys
[.]		:Decimal point key
[+]		:Add key
[-]		:Subtract key
[×]		:Multiplication key
[÷]		:Division key
[=]		:Equal key
[%±]		:Percent key
[MS]		:Memory subtotal recall key
[MT]		:Memory total clear key
[M+]		:Memory plus key
[M-]		:Memory minus key
[D/#]		:Date/Number key print key
[	]	:Paper feed key
[	/S]	:Subtotal key
[C/CE]		:Clear last calculation/Clear last entry
[	]	:Back space key
[	]	:Inverts sign of the displayed number at
		Key entry
[TAX+] or [TAX-]		:TAX+ Calculates the amount, using the
		stored rate, and adds it to the original
		price before tax
		TAX- Calculates the amount of tax
		to be deducted (using the stored tax
		displayed value to find the pre-tax
		sales amount
		Prints TAX / Included TAX (TAX=3)
		A	TAX+		= A(3/100)
					= A+(A(3/100))
		Prints TAX / excluded TAX(TAX=3)
			A	TAX-		= A - A (1+3/100)
					= A / (1+3/100)
[∆%]		:Prints difference (Computes the %
		of change between two values)
			A	∆%	B	= B - A
						= (B - A) / A
			A	∆%	B +/-	= - (B + A)
[*/T]		: Total key				= - (B + A) / A

[COST] [MARGIN] [SELL] :Used for calculating the cost,