Question

Only 10% of the carbon-14 in a wooden bowl remains. How old is the bowl(rounded to the nearest hundred years, and use 5700 years as a carbon-14's half-life)?

Answer 1

.5=e^-5700k
ln .5=ln e^-5700k=-5700k ln e=-5700k
k=.00012160476
.1=e^-.00012160476t
ln .1=ln e^-.00012160476t=-0.00012160476t ln e=-0.00012160476t
t=18,935 years as the age of the bowl