Given that 1 hour and 30 minutes can be expressed as 90 minutes, then we can replace t=90 in the equation to find the temperature. Doing so, we have:
[tex]\begin{gathered} T(t)=61e^{-0.0174t}+75. \\ T(90)=61e^{-0.0174(90)}+75.\text{ (Replacing)} \end{gathered}[/tex][tex]\begin{gathered} T(90)=61e^{-1.566}^{}+75.(\text{ Multiplying)} \\ T(90)=61\cdot0.209+75\text{ (Raising e to the power of -1.566)} \\ T(90)=12.74+75\text{ (Multiplying)} \\ T(90)=87.74\text{ (Adding)} \end{gathered}[/tex]The answer would be 88 in degrees Farenheit. (Rounding to the nearest whole number)
