The general form of the decay equation is S = S_{o}e-kt

where

S = amount remaining, S_{o} = the initial amount, k = decay constant, & t = time in years

Then to find k: (assume we start with 100 lbs as the intial amount & have half left)

50 = 100e^{-k(5750)} or 1/2 = e^{-k(5750)} Solving for k = .00012055

To find the age of the bones, assume we start with 100 lbs of bones

Then

59.7 = 100e^{-(.00012055)t } Solving for t = 4,279 years