Answer:
Aight bet, so it's 74 degrees Fahrenheit at the moment, and it takes one hour for it to increase by 2 degrees, so what I would do, is 87 minus 74, which equals to 13, 13 is an odd number of course, but, let's put it at 12 first and do the remaining 1 later, so it's 12, so divide 12 by 2, equals to 6, so for now, 6 hours, then, the remaining 1 degree, as it takes two degrees PER hour, and 1 is half of 2, 1 degree will take 30 mins, so 6 hours and 30 mins.
It will take 6 hours and 30 minutes for the temperature from 74 degrees to increase to 87 degrees.
Explanation: