Final answer:
Approximately 98.8 milligrams of the vitamin would remain in the bloodstream 6 hours after the peak level, calculated using the exponential decay formula with an 18% hourly decay rate.
Step-by-step explanation:
To predict the amount of a vitamin remaining in the bloodstream 6 hours after its peak level, we use the concept of exponential decay. The decay rate is 18% per hour, which means that each hour, the vitamin's concentration becomes 82% (100% - 18%) of what it was the previous hour. Starting with a peak level of 325 milligrams, we can apply the decay formula repeatedly for 6 hours.
The formula for exponential decay is: New amount = Initial amount * (1 - decay rate)^time.
In this case, we calculate the remaining amount after 6 hours using the formula: Remaining amount = 325 mg * (1 - 0.18)^6.
Calculation:
Remaining amount = 325 mg * (0.82)^6
Remaining amount = 325 mg * 0.304006
Remaining amount ≈ 98.8 mg
To the nearest tenth of a milligram, about 98.8 milligrams of the vitamin would remain in the bloodstream after 6 hours.