What decimal is modeled? 5 into 5

An archaeologist in turkey discovers a spear head that contains 53% of its original amount of c-14. find the age of the spear head to the nearest year. (5250 isn’t right)

On the blueprint of a house, 42 millimeters represents 8 meters. the actual lehenth of the living room is 5 meters. what is the length on the blueprint

Someone me and explain! will award brainliest!