Answer:
The average temperature is 
Step-by-step explanation:
From the question we are told that
The temperature of the coffee after time t is ![T(t) = 25 + 72 e^{[-\frac{t}{45} ]}](https://tex.z-dn.net/?f=T%28t%29%20%3D%20%2025%20%2B%2072%20e%5E%7B%5B-%5Cfrac%7Bt%7D%7B45%7D%20%5D%7D)
Now the average temperature during the first 22 minutes i.e fro 
minutes is mathematically evaluated as
![T_{a} = \frac{1}{22-0} \int\limits^{22}_{0} {25 +72 e^{[-\frac{t}{45} ]}} \, dx](https://tex.z-dn.net/?f=T_%7Ba%7D%20%3D%20%20%5Cfrac%7B1%7D%7B22-0%7D%20%20%5Cint%5Climits%5E%7B22%7D_%7B0%7D%20%7B25%20%2B72%20e%5E%7B%5B-%5Cfrac%7Bt%7D%7B45%7D%20%5D%7D%7D%20%5C%2C%20dx)
![T_{a} = \frac{1}{22} [25 t + 72 [\frac{e^{[-\frac{t}{45} ]}}{-\frac{1}{45} } ] ] \left| 22} \atop {0}} \right.](https://tex.z-dn.net/?f=T_%7Ba%7D%20%3D%20%5Cfrac%7B1%7D%7B22%7D%20%5B25%20t%20%20%2B%20%2072%20%5B%5Cfrac%7Be%5E%7B%5B-%5Cfrac%7Bt%7D%7B45%7D%20%5D%7D%7D%7B-%5Cfrac%7B1%7D%7B45%7D%20%7D%20%5D%20%5D%20%5Cleft%7C%2022%7D%20%5Catop%20%7B0%7D%7D%20%5Cright.)
![T_{a} = \frac{1}{22} [25 t - 3240e^{[-\frac{t}{45} ]} ] \left | 45} \atop {{0}} \right.](https://tex.z-dn.net/?f=T_%7Ba%7D%20%3D%20%5Cfrac%7B1%7D%7B22%7D%20%5B25%20t%20%20-%203240e%5E%7B%5B-%5Cfrac%7Bt%7D%7B45%7D%20%5D%7D%20%5D%20%5Cleft%20%7C%2045%7D%20%5Catop%20%7B%7B0%7D%7D%20%5Cright.)
![T_{a} = \frac{1}{22} [25 (22) - 3240e^{[-\frac{22}{45} ]} - (- 3240e^{0} )]](https://tex.z-dn.net/?f=T_%7Ba%7D%20%3D%20%5Cfrac%7B1%7D%7B22%7D%20%5B25%20%2822%29%20%20-%203240e%5E%7B%5B-%5Cfrac%7B22%7D%7B45%7D%20%5D%7D%20%20%20-%20%28-%203240e%5E%7B0%7D%20%29%5D)
![T_{a} = \frac{1}{22} [550 - 1987.12 + 3240]](https://tex.z-dn.net/?f=T_%7Ba%7D%20%3D%20%5Cfrac%7B1%7D%7B22%7D%20%5B550%20%20-%201987.12%20%20%2B%20%203240%5D)
There are 4 equal slices because 25 to 25 to 25 to 25 =100
J=30 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
It would be -15.4 rounding to the nearest hundredth
