# What is the temperature?

Question. The temperature of an object in degrees Fahrenheit after t minutes is represented by the equation T(t) = 68e-0.0174t + 72. To the nearest degree, what is the temperature of the object after one and a half hours?

How to solve this question?

What is the formula?

Update:

revised : T(t) = 68e^-0.0174t + 72

Relevance
• You have the formula, but let me correct your notation slightly:

T(t) = 68e^(-0.0174t) + 72

Also, the time (t) is given in *minutes*.

1.5 hours = 90 minutes

T(90) = 68e^(-0.0174*90) + 72

T(90) ≈ 86°F

Note: If you graph it, you'll see that the temperature starts at 140°F and is asymptotically approaching the ambient room temperature of 72°F. After 1½ hours (90 minutes), it has cooled down to about 86°F

Update:

Your revised equation is still technically incorrect. You need to include the t inside parentheses. The exponent takes precedence over the multiplication by t if you don't group the two together.  Example: 2^(3t) is different than 2^3t = (2^3)t = 8t

• t is in minutes. So at a time of one and a half hours, how many minutes is that?

Now, replace this value you just found by "t" and put it in the formula & compute.

What do you finally get?

Done!

Hopefully no one will spoil you the answer thereby depriving you from your personal enhancement; that would be very inconsiderate of them.