Using the "+ tax" Key

The "+ tax" is used for percentage calculations for a fixed, often used percentage like calculating sales tax.
The benefit of using this key is that the subtotal and tax are rounded to the current format settings to prevent rounding errors that will occure using the % key.

You store the sales tax rate once, then you can calculate the tax and total with one key stroke.

These examples use the Percentages Calculator

To	Press (CHN, ALG or RPN)	Display x	Display y
Store a percentage of 6.75%	6.75 STO Pct	6.75
Calculate "tax and total" on 100	100 + tax	106.75	6.75
Calculate "tax and total" on a calculated result.	122.22482436 + tax	130.47	8.25

In this last example, 122.22482436 is from a calculated result.
If the tax was calculated using the percent key, (+6.75%, 8.25) the result would be 130.475. This would be rounded to 130.48 with fix(2) display format and look like an addition error..

In CHN or RPN mode, the y value is displayed if you have more than 1 row of the stack displayed.

In ALG mode, tap SWAP to see the y value. Pressing SWAP swaps the x and y registers.

The History details will have a record of the calculations that you can view and share.