Problema Solution
You have 960 grams of a radioactive kind of selenium. How much will be left after 360 days if its half-life is 120 days?
Answer provided by our tutors
We know that a half life is 120 days, and our time span is 360 days. So 360/120=3. We will complete 3 half-lives in this time period:
starting with 960 grams
after 120 days there will be: 480 g
after another 120 days (in total 240 days) there will be: 240 g
after another 120 days (in total 360 days) there will be: 120 g of radioactive kind of selenium left.