The​ half-life of radium is 1690 years. If 50 grams are present​ now, how much will be present in 60 ​years?

Answer 1

m(t) = m₀e^rt; m₀/2 = m₀e^1690r; r = ln(1/2)/1690 = - 0.00041015

m(60) = 50·e^{-0.00041015·60} = 48.785 g