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## #1 Help Me ! » Working backwards from a formula » 2005-09-17 04:33:08

Sten
Replies: 1

I've always been terrible at working backwards from a formula.

units = 300 * (growingNumber^1.1)

The above formula determines how many units a certain item requires to complete. Each additional item increases in unit consumption to complete. My task is to determine a formula that will return the total number of items that can be built, given a certain number of units.

ie.
The above formula produces:
Item#  Units
1     300
2     643
3     1,005
4     1,378
5     1,762
6     2,153
7     2,551
8     2,955
9     3,363
10     3,777

If a person has 5008 units, he can then produce 5 total Items (300+643+1005+1378+1762 = 5008).

How can I create a formula to determine that 5 total items can be produced with 5008 units, without actually calculating up every unit cost per item?

Any help would be greatly appreciated.

Regards,
Sten