I am working on creating a calculated field on a form which has limited mathematical capabilities. My available operators are: + - / * ( ). My calculated field is based on the value of two drop down menus where a user selects how many children they are signing up for a club.
Regardless the summation works like this the first participant is 120, the second is 100 and after that each additional participant is 80.
- 1 participants (120) = 120
- 2 participants (120 + 100) = 220
- 3 participants (120 + 100 + 80) = 300
- 4 participants (120 + 100 + 80 + 80) = 380
- 5 participants (120 + 100 + 80 + 80 + 80) = 460
- 6 participants (120 + 100 + 80 + 80 + 80 + 80) = 540
- 7 participants (120 + 100 + 80 + 80 + 80 + 80 + 80) = 620
- 8 participants (120 + 100 + 80 + 80 + 80 + 80 + 80 + 80) = 700
- 9 participants (120 + 100 + 80 + 80 + 80 + 80 + 80 + 80 + 80) = 780
- 10 participants (120 + 100 + 80 + 80 + 80 + 80 + 80 + 80 + 80 + 80) = 860
Is this sort of formula possible given the limited operators? Right now both drop downs are limited to 5 participants for a maximum total of 10 between the two fields.
For $n$ participants where $n \geq 3$
the sum is
$220+(n-2)t$