suppose it is 40° inside your refrigerator and 340° inside your oven the power goes out. The refrigerator temperature starts rising at the rate of 5° per hour. the oven temperature starts dropping at the rate of 45° per hour. how long will it take for the temperature to be the smae?
First see: 1 hour-5' rise for refrigerator 1 hour - 45' drop for oven Than: 40' inside refrigerator / 340' inside the oven Than, just minus 45' for the oven for per hour than plus 5' for the refrigerator per hour