These are based on the standard formula from elementary maths for the sum of terms in a geometric progression, where
a = first term
n = number of terms
r = ratio between successive terms
The sum is a(r^n -1)/(r-1)
(1) Cost of acquiring n of a building
C = cost of next building
r = 1.15
cost of n buildings is C*(1.15^n - 1)/0.15
(2) Cost of replacing n buildings (eg. after sacrificing 100 to unlock an aura)
Here we are going down the sequence instead of up. Each building is cheaper than the one before. Here r = 1/1.15
cost = C/1.15 * (1/1.15^n - 1)/(1/1.15 - 1)
= C * (1 - 1/1,15^n)/0.15
n is normally 50, 100, or 200, making the term 1/1.15^n so tiny that the cost is effectively just C/0.15.
(3) Cookies released by selling n of a building
Just multiply the formula in (2) by the resale factor f:
Cookies released = f * C * (1 - 1/1,15^n)/0.15
f = 0.5 (or 0.85 if Earth Shatterer is active).
Cookies obtained from selling ALL buildings, if you have more than a couple of dozen of them, is very close to f * C/0.15.
Post edited by bob_32_116 on