A patient is given a 50 mg dose of medicine. The medicine's effectiveness decreases every hour at a constant rate of 40%. What is the exponential decay function that models this scenario? How much medicine will be left in the patient's system after 2 hours?
A.f(x) = 50(0.40)x; 8 mg
B.f(x) = 50(0.60)x; 18 mg
C.f(x) = 50(40)x; 80,000 mg
D.f(x) = 50(60)x; 180,000 mg
(X is a exponent)

Question

A patient is given a 50 mg dose of medicine. The medicine's effectiveness decreases every hour at a constant rate of 40%. What is the exponential decay function that models this scenario? How much medicine will be left in the patient's system after 2 hours? 
A.f(x) = 50(0.40)x; 8 mg
B.f(x) = 50(0.60)x; 18 mg
C.f(x) = 50(40)x;  80,000 mg
D.f(x) = 50(60)x; 180,000 mg
(X is a exponent)

anonymous · Answer

which one do you think is you answer?

anonymous · Answer

d?

anonymous · Answer

The patient only got 50 mg to begin with, so that eliminates C and D.

anonymous · Answer

I'm pretty sure the exponential decay equation is
f(x) = (initial amount)(1 - rate)^x
where the rate is written as a decimal