Answer:
7.5 hours
Step-by-step explanation:
We can model an equation for this problem.
We can write:
Where
F is the final temperature (15 degrees we need)
m is the rate of temperature change (2 degrees per hour)
and
t is the time, in hours, it will take (we need to find this)
It is given,
F = 15
m = 2
So, t would be:
F = mt
15 = 2t
t = 15/2 = 7.5
So it will take 7.5 hours