1. The problem statement, all variables and given/known data A small animal bone fragment found in an archaelogical site has a carbon mass of 155g. When the animal was alive, the ratio of radioactive 146C to the stable 126C was 1.31×10-12. What was the number of 146C nuclei found in the sample when the animal was alive? 2. Relevant equations None given, but I would assume: N=N0e-λt 3. The attempt at a solution Not too sure where to start so I got the decay constant, λ by using half life of Carbon14, 5730 Years 0.5=e-λ(5730) λ=1.21×10-4 Then I solved the for the number of years since the animal was alive by plugging everything back into the original equation, assuming N/N0 = 1.31×10-12 t=-ln(1.31×10-12)/-1.21×10-4 = 226180 Years Up until here I don't think I did anything wrong, but here is where I am unsure of what to do. I tried using the same formula to solve for N0, but this time using the given 155g. 155=N0e-(1.2110-4)(226180) N0=1.18×1014g I don't think in doing the right thing here. Can anyone give me some guidance? Thanks!