Answer:
187.5 milligrams of a 1500 mg sample will remain after 180 days
Explanation:
Given:
Half life of Iodine-125 = 60 days
Initial amount of Iodine-125 present = 1500mg
To Find:
The amount of Iodine-125 present after 180 days
Solution:
Half- life the time taken for the radioactive substance to decay or reduce into half of its amount.
So,
After first 60 days
=>

After next 60 days i.e., after 120 days
=>

After another 60 days i.e., after 180 days
=>
