Answer:
Number of years between 1950 and 2100 =
[tex]2100 - 1950 = 150 \: years[/tex]
150 = 50 + 50 + 50 years.
[tex]2500000 \times 150 = 375,000,000[/tex]
So, total population in 2100 is 375,000,000.