Answer:
360 mg.
Step-by-step explanation:
The medicine has a decay rate of 40% in 25 hours, which means after 24 hours its amount will be 100% - 40% = 60% it's original value.
Let us call [tex]t[/tex] the number of hours passed and [tex]d[/tex] the number of 24-hours passed, then we know that
[tex]t = 24d[/tex].
Now, the amount [tex]c[/tex] of medicine left after time [tex]d[/tex] (dth 24-hour) will be
[tex]c = 1000(0.6)^d[/tex]
and since [tex]t =24d[/tex], we have
[tex]$\boxed{c = 1000(0.6)^{\frac{t}{24} }}$[/tex]
We now use this equation to find the final amount after [tex]t =48 hours[/tex]:
[tex]c = 1000(0.6)^{\frac{48}{24} }[/tex]
[tex]c = 1000(0.6)^2 }[/tex]
[tex]\boxed{c =360mg}[/tex]
