half-life

The half-life of a radioactive substance is 24 hours and there are 100 grams initially. What is the amount of substance remaining after one week? Using our half life calculator converting to days since 24 hours is 1 day and one week is 7 days, we have: 0.78125

Rosanne takes 190 milligrams of an antibiotic. Every hour, her body breaks down 50% of the drug. How much will be left after 5 hours Let the antibiotic amount be A(h) where h is the amount of hours after ingestion. We have: A(h) = 190 * (1 - 0.5)^h A(h) = 190 * (0.5)^h The problem asks for...

The anti-inflammation drug Advil has a half-life of 2 hours. That is, the amount of the drug present in the body is halved every two hours. What fraction of the initial amount of the drug will be left in the body after 4 hours? At time 0, we have 100% At time 2, we have 100% * 1/2 = 50% or...

You have 240 grams of a radioactive kind of tellurium. How much will be left after 210 minutes if its half-life is 70 minutes? if the half life is 70 minutes, then we have 210/70 = 3 half life cycles. So the first half-life is 240 * 1/2 = 120 The second half life is 120 * 1/2 = 60 The third...

The half-life of radioactive kind of manganese is 6 days. How much will be left 18 days, if you start with 80 grams of it? Using our half-life calculator, we get size 10.