MHB Solve 1st-Order ODE: Chicken in 375° Oven

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The discussion revolves around solving a first-order ordinary differential equation (ODE) based on Newton's law of cooling to determine when a chicken reaches 150 degrees in a 375-degree oven. The equation \(\frac{dT}{dt}=k(A-T)\) is established, with initial conditions provided: the chicken starts at 50 degrees and reaches 125 degrees after 75 minutes. The user expresses confusion over the correct approach to solving the ODE, initially deriving a general solution but questioning the validity of using multiple initial conditions to find constants. Another participant suggests separating variables and using the initial conditions to solve for the time variable \(kt\) directly, which would yield the desired time for the chicken to reach 150 degrees. The conversation emphasizes the importance of correctly applying initial conditions and solving for constants in the context of the problem.
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I'm going to need a little help with this one. I get an answer but it doesn't make sense. The question states

According to Newton's law of cooling, the time rate of change of temperature T(t) of a body immersed in a medium of constant temperature A is proportional to the difference A-T. That is [math]\frac{dT}{dt}=k(A-T)[/math] where k is a positive constant. A 3lb chicken is initially 50 degrees, is put into a 375 deg oven. After 75 minutes it is found that the chicken is 125 deg. When will it be 150 deg?

I may have gone astray right away. Are we trying to solve the differential equation and find T(t)? I found it to be [math]T=A+\frac{C}{e^{kt}}[/math] and then using initial condition T(0)=50 found [math]T=A+\frac{50-A}{e^{kt}}[/math] Then we know T(75)=125. This let's us solve for k. Hold on a sec, :confused: basically I just used one IC to solve for C and another to solve for K. I'm not sure that's right.
 
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We really don't need to find $T$, what I would do to answer this question is separate variables, use the initial conditions and solve for $kt$, then use the other known point on the curve to solve for $k$, and then you will have $t$ as a function of $T$.
 

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