Answer: Choice D) 281.25 mg
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Work Shown:
Plug in t = 2 and we get the following
The answer is choice D. There are 281.25 mg of aspirin in the bloodstream after 2 hours.
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Side notes:
- The 500 represents the initial amount of aspirin (in mg) in the bloodstream. This is the amount when t = 0.
- The 3/4 converts to 0.75; when solving 1+r = 0.75, we get r = -0.25, and this shows a 25% reduction in aspirin each time t goes up by 1. Every hour, the amount of aspirin in the bloodstream reduces by 25%