math
posted by Anonymous .
An artifact was found and tested for its carbon14 content. If 76% of the original carbon14 was still present, what is its probable age (to the nearest 100 years)? Use that carbon14 has a halflife of 5,730 years.

.76 = 1(1/2)^(t/5730)
ln both sides
ln .76 = ln (.5)^(t/5730)
t/5730 ln.5 = ln.76
t/5730 = ln.76/ln.5 = .3959..
t =2268.67
age is appr. 2269 years