Deduce the relation between half life and average life of a radioactive substance.

Give the relation between half life and mean life

Distinguish between half and average life of a radioactive substance.

(a) Differentiate between half-life and average life of a radioactive substance. (b) A radioactive substance decays for an interval of time equal to its mean life. Find the fraction of the amount of the substance which is left undecayed after this time interval.