20% of a radioactive substances decay in 10 days . Calculate the amount of the original material left after 30 days.

If 10% of a radioactive material decays in 5 days, then the amount of original material left after 20 days is approximately.

If 10% of a radioactive material decays in 5 days, then the amount of original material left after 20 days is approximately.

Half-life of a radioactive substance is 2.9 days. Calculate the amount of 10 mg of substance left after 29 days.

If 20% of a radioactive sample decays in 10 days, then the amount of substance left after 20 days will be approximately

A radioactive substance has a halflife of 50 days . Fraction of the material left behind after 100 day will be :

A radioactive substance has decay constant of 0.231 "day"^(-1) . Calculate the percentage of the substance left after 6 days.