HP 12c Solutions Handbook page 97

list and new and several discounts are known it may be desirable to calculate
a missing discount. The following series of keystrokes may be used:
1. Key in 1, press
2. Key in the first discount (as a percentage) and press
.
3. Repeat step 2 for each of the remaining known discount rates.
4. To calculate the list price, key in the net price and press
5. To calculate the net price, key in the list price and press
6. To calculate an unknown discount rate, immediately after doing step 3
(display should show 1.00), key in the net price, press
in the list price.
7. Press
Example: The list price of an item is $3.28 and the net price is $1.45. Two
of the discount rates are 48% and 5%. What is the third discount rate?
Keystrokes
1
1
48
5
1.45
3.28 1
100
The following program for the HP 12C will be helpful in performing the
calculations:
KEYSTROKES
CLEAR
1
1 100
Display
1.00
1
1.00
1
1.00
0.49
10.51
.
3rd discount rate (%).
DISPLAY
00-
01-
02- 34
03- 25
96
1.
1
1
and key
1
1
.
.