SOLUTION: I tried to do this problem with the example from the site, yet couldn't find the right answer. Please I need help on this!! A roasted turkey is taken from an oven when its tempe

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Question 1176054: I tried to do this problem with the example from the site, yet couldn't find the right answer. Please I need help on this!!
A roasted turkey is taken from an oven when its temperature has reached 185 Fahrenheit and is placed on a table in a room where the temperature is 75 Fahrenheit. Give answers accurate to at least 2 decimal places.
(a) If the temperature of the turkey is 150 Fahrenheit after half an hour, what is its temperature after 45 minutes?

(b) When will the turkey cool to 100 Fahrenheit?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
F(t)=Fs+(Fo-Fs)*e^(-kt)
150=75+(185-75)e^(-30k)
75=110e^(-30k)
(75/110)=15/22=e^(-30k)
ln both sides
-0.3830=-30k
0.012767=k, but round at the end
-
F(45)=75+(110)*e^(-40*0.012767)
e^(-0.51067)=0.60001
110*0.60001=66.00
add to 75 and temperature is 141.00 degrees
-
100=75+110*e^(-0.012767*t)
25/110=5/22=e^(-0.012767*t)
ln both sides
-1.4816=-0.012767t
t=116.05 minutes