Answer: 360 mg of the medicine will be detected after 48 hours
Step-by-step explanation:
We would apply the formula for exponential decay which is expressed as
A = P(1 - r)^t
Where
P represents the initial dosage of the medicine.
A represents the final dosage of the medicine after t hours.
t represents the number of hours.
r represents the rate of decay
From the information given
P = 1000 mg
r = 40% = 40/100 = 0.4
The expression becomes
A = 1000(1 - 0.4)^t
A = 1000(0.6)^t
In 48 hours, t = 2
Therefore,
A = 1000(0.6)^2
A = 360