Answer:
Amount of caffeine left after 5 hours = 36 mg
Step-by-step explanation:
We are told that the cup has 310 mg of caffeine originally.
Since it decreases by 35 percent or 0.35 each hour, it means that for each additional hour, the new amount of caffeine would be (1 - 0.35) x previous amount i.e. 0.65 x previous amount. Thus;
After 0 hour, we have; 310 mg
After 1 hour, we have; 310(0.65)
After 2 hours, we have; 310(0.65)(0.65)
After 3 hours, we have; 310(0.65)(0.65)(0.65)
We can see this follows a pattern of;
A(t) = 310(0.65)^(t)
Where;
A(t) is the amount left after t hours
And t is time t hours
Thus, amount left after 5 hours is;
A(5) = 310(0.65)^(5)
A(5) = 310 x 0.11603
A(5) ≈ 36 mg
Answer:
36 mg
Step-by-step explanation:
Please refer to the attached image for explanations
