How to Calculate Final Temperature in a Water and Aluminum System?

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Homework Statement



160 grams of boiling water (temperature 100° C, heat capacity 4.2 J/gram/K) are poured into an aluminum pan whose mass is 950 grams and initial temperature 26° C (the heat capacity of aluminum is 0.9 J/gram/K).
(a) After a short time, what is the temperature of the water?



Homework Equations



ΔE = ΔKsys + Δ(Msysc^2) + ΔUsys + ΔEint = Wsurr + Q

Wsurr + Q = 0 because the surroundings aren't effecting the problem, and ΔEint isn't changing.

ΔEint = 0

So...

m1C1*ΔT + m2C2*ΔT = 0

m1C1(Tf - 373.15K) + m2C2(Tf - 299.15K) = 0




From there I don't know what to do. I know I have to solve for Tf, but I guess my problem is I don't know how to solve for Tf.

I know that Tf is the same for both of them, but that doesn't really help me solve for it. I'm probably just not thinking straight right now.

The Attempt at a Solution



Couldn't get an answer because I can't figure out how to solve for Tf.
 
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This looks right, m1C1(Tf - 373.15) + m2C2(Tf - 299.15) = 0
so rearranging terms this gives Tf(m1C1-m2C2) = 373.15m 1C1-299.15 m2C2

Tf = (373.15 m1C1-299.15 m2C2)/(m1C1-m2C2)
 
It took a while, but it actually equals:

Tf=373.15m1c1+299.15m2c2/m2 + c2