The population of a town increases geometrically with time. According to the 1980 demographic census, the town population was 150,000 inhabitants, whereas the 2000 census counted 205,000 people. An...

The population of a town increases geometrically with time. According to the 1980 demographic census, the town population was 150,000 inhabitants, whereas the 2000 census counted 205,000 people. An engineer wants to check the operative conditions of the local water supply system at an intermediate point in time. To do it he/she needs an estimate of the 1990 population to calculate the per capita water consumption. Determine the central value needed by the engineer. Justify your answer