Correct answer is: A) [tex]\frac{-15F}{13hours}[/tex]
Solution:-
Given that temperature of town increased 16 Fahrenheit in 5 hours and decreases 31 Fahrenheit in the next 8 hours.
If we assume T as temperature, it became T+16 in 5 hours and (T+16-31) in next 8 hours.
That is change in temperature in (5+8) hours is 16-31 = -15 Fahrenheit.
Rate of total change in temperature = [tex]\frac{change in temperature}{time}[/tex]
                              = [tex]\frac{-15}{5+8}=\frac{-15}{13}[/tex]
Hence rate of total change in temperature is [tex]\frac{-15F}{13hours}[/tex]
