Question

At a given instant, there are `25%` undecayed radio-active nuclei in a sample. After `8 sec`, the number of undecayed nuclei reduced to `12.5%`. The time after which the number of undecayed unclei will further reduce to `6.25%` of the reduced number is ______sec

Answer 1

To reduced by half number the time required`=` one half life`=8 sec`