a radioactive material is reduced to 1/16th of its original amount in 4 days how much material should - Physics - Dual Nature of Radiation and Matter

Question

a radioactive material is reduced to 1/16th of its original amount
in 4 days how much material should one begin with so that 4 * 10^-3
kg of the material is left after 6 days can someone else ans this
question

Sanjay Singh · Accepted Answer

Dear student
Mass of radioactive sample left after n half life   m(t)=initial mass2n =m02n       (where n is number of half life)No of half life in time t  is n=tT12        as time elapsed t=n×T12m(t)=initial mass2n=m02nAfter 4 days mass reduces to 116 of itsinitial value means m(t)=m016  so putting in eqn 
1m016=initial mass2n=m02nn=4n=4T124=4T12T12=1dayGiven mass remaining after 6 days=4×10-3kgm(t)=initial mass2nin this case number of half life n=61m(t)=m02n=m0264×10-3=m064m0=0
256 kgSo we should begin with a mass of 0
256 kg Regards

a radioactive material is reduced to 1/16th of its original amount in 4 days . how much material should one begin with so that 4 * 10^-3 kg of the material is left after 6 days...can someone else ans this question