We have the following:
The first thing is to calculate what the 12.2 days represent with respect to its half-life, which is 3.8 days, therefore
[tex]\frac{12.2}{3.8}=3.2[/tex]
Therefore it represents 3.2 times the half life of the compound, therefore 100 grams would remain:
[tex]100\cdot\mleft(\frac{1}{2}\mright)^{3.2}=10.88[/tex]
Therefore there would be a total of 10.88 grams
