<PRE><B>Question 1130985</B>
This is your formula as stated:  T(t) = 70(0.727)t


More likely the formula you are given is T(t) = 70(0.727)^t and appears when rendered as  {{{T(t) = 70(0.727)^t}}}.




(a) :
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How much, to the nearest milligram, of the anesthetic is present in the patient&#39;s circulatory system 20 minutes after the anesthetic is administered?_____mg
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20 minutes is {{{1/3}}}{{{hour}}}, so evaluate T for {{{t=1/3}}}.



(b):
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How long, to the nearest minute, can the operation last if the patient does not receive additional anesthetic?
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This means, {{{T(t)=50}}}, and yuo want to solve for t.
Try taking logs of both sides of the equation to start this.  Remember, you are finding t in HOURS so convert your solution into minutes.</PRE>