It takes 10 years for the substance z to decay from 48g to 3g
Half life of z = 2.5 years
Final amount of Z = 3 g
Initial amount of Z = 48 g
According to the question, it takes 2.5 years for substance Z to reduce to half.
So,
In 2.5 years, the amount of z = 48/2 = 24 grams
In next 2.5 years, the amount of z = 24/2=12g
In next 2.5 years, the amount of z = 12/2=6g
In next 2.5 years, the amount of z = 6/2=3g
To reduce the amount from 48g to 3g, total years = 2.5 + 2.5 + 2.5 + 2.5
= 10 years
Therefore, it takes 10 years for the substance z to decay from 48g to 3g
