Please explain how to change the value on the tax function on a Busicom EL-2878b calculator Thank you

SOURCE: Changing the % tax setting on my Casio calculator

step 1 pess the AC button step 2 press and hold for two seconds the % button step 3 press the tax+ button step 4 input 17­.5 step 5 press the % button that should be the tax set you can check it is set correctly by pressing the AC button and then the tax+ and 17.5 should be displayed

SOURCE: Need to change tax function on Sharp EL-334A

I had the same problem and finally figured it out. Here's what you do:

Press C-CE twice
Press +TAX (Rate set)
Key in your new tax rate as an integer (e.g. 5)
Press +Tax (Rate set) again
Press C-CE

Then you're ready to calculate with the new rate!

Now what's the GT button for?

SOURCE: CHANGE TAX %+ & TAX- ON MY CASIO JF-100TE CALCULATOR

1. Press [AC]
2. Hold [SET/%] key for about 2 seconds
3. Press [TAX+]
4. Input the tax rate
5. Press [SET/%]

SOURCE: Viking V714 calculator tax rate change

1. Press C button
2. Press 1 then 5 button for the 15% VAT rate - 15 is shown on screen
3 Press SET Button
4. Press TAX+ button
5 Press = Button - 15.00 is shown on screen

All is done, check by doing:
C
100
TAX+

answer will be 115.00

Press TAX+ again- answer is 15.00

SOURCE: change the tax rate on calculator on MS-8TV

SETTING YOUR TAX RATE
you hold your set % button down for three seconds until set shows again, then hit tax rate button it shows your tax rate, change your tax rate then hit set your tax rate should be set.



cliff notes:
hold set% button
hit tax+ button
change the desired % 
hit set done


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