9514 1404 393
Answer:
about 145.3 mg
Explanation:
If half breaks down in the hour, then half remains. That is, each hour the amount remaining is multiplied by 1/2. The remainder after 6 hours is ...
(9300 mg)(1/2)^6 = 145.3125 gm
About 145.3 mg will be left after 6 hours.