Answer:
The answer to your question is 3.75 mg
Step-by-step explanation:
Data
Radium-223
half-life = 11 days
mass = 60 mg
total time = 44 days
Process
1.- Draw a chart to start the calculation
Mass Number of days Half-lives
60 mg 0 0
30 mg 11 1
15 mg 11 2
7.5 mg 11 3
3.75 mg 11 4
Total number of days 44
Mass active after 44 days = 3.75 mg