Answer:
Number of people that will be infected in 4 years is 252,610.
Step-by-step explanation:
The number of people that will be infected in 4 years can be calculated as follows:
Number of people that will be infected in year 1 = 160,000
Number of people that will not be infected in year 1 = 400,000 - 160,000 = 240,000
Number of people that will be infected in year 2 = Number of people that will not be infected in year 1 * 15% = 240,000 * 15% = 36,000
Number of people that will not be infected in year 2 = Number of people that will not be infected in year 1 - Number of people that will be infected in year 2 = 240,000 - 36,000 = 204,000
Number of people that will be infected in year 3 = Number of people that will not be infected in year 2 * 15% = 204,000 * 15% = 30,600
Number of people that will not be infected in year 3 = Number of people that will not be infected in year 2 - Number of people that will be infected in year 3 = 204,000 - 30,600 = 173,400
Number of people that will be infected in year 4 = Number of people that will not be infected in year 3 * 15% = 173,400 * 15% = 26,010
Therefore, we have:
Number of people that will be infected in 4 years = Number of people that will be infected in year 1 + Number of people that will be infected in year 2 + Number of people that will be infected in year 3 + Number of people that will be infected in year 4 = 160,000 + 36,000 + 30,600 + 26,010 = 252,610
