SOLUTION: Story problem: A can of soda at 79 degrees F is placed in a refrigerator that maintains a constant temperature of 36 degrees F. The temperature T of the soda t minutes after it i

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Question 151178: Story problem: A can of soda at 79 degrees F is placed in a refrigerator that maintains a constant temperature of 36 degrees F. The temperature T of the soda t minutes after it is placed in the refrigerator is given by T(t)=36+43e^-.058t.
Part a) Find the temperature to the nearest degree of the soda 10 minutes after it is placed in the refrigerator.
I substituted 10 into the equation and got 60 degrees F. I understand this part.
Part b) When, to the nearest minute, will the temperature of the soda be 45 degrees F? HELP! I think that you need to plug in equations to graph it but I don't know what to plug in.
Thanks,
Rose
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
You are correct on part a
Part b asks when the temp will be 45 degrees
GivenT%28t%29=36%2B43e%5E%28-.058t%29
45=36%2B43e%5E%28-.058t%29
9+=+43e%5E%28-.058t%29
9%2F43+=+e%5E%28-.058t%29
0.209+=+e%5E%28-.058t%29
ln%280.209%29+=+ln%28e%5E%28-.058t%29%29
-1.565+=+-.058t
1.565%2F0.058+=+t
1.565%2F0.058+=+27
about 27 minutes later.
Check your answer by plugging 27 into the original equation