Question

Can anyone help me understand this Newtons Law of Cooling problem?

Answer 1

On a hot day, a thermometer was brought outdoors from an air-conditioned building. The temperature inside the building was 21C, and so this is what the thermometer read at the moment it was brought outside. One minute later the thermometer read 27C, and a minute after that it read 31C. What was the temperature outside? (Impress us and express the answer without using logarithms or the number e)