The initial amount of radioactive substance is 52 grams. The substance decays at a rate of 1%. After 12 years, how many grams of the substance is present? Approximate to the nearest gram.
If the rate of decay is 1% per year, the number of grams present after 12 years is found from: [tex]52\times(0.99)^{12}=46\ grams[/tex] An alternative solution can use the following equation: [tex]N(t)= N_{0} e^{-\lambda t}[/tex] Plugging in given values, we get: [tex]N=52\times e^{-0.01\times t}=46\ grams[/tex]
