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Solution to Problem Set 1
1) 102000
r * N so 7.5 * 12000 = 9000 growth. Add growth to start population so 90000 + 12000
2) 21218
r * N so after 1 year growth = 0.03 * 20000 = 600 so the population is 20600
after two years 0.03 * 20600 = 618 so the population is 21218
3) 13860
r * N so -0.01 * 14000 = -140 so population equals 14000 + (-140)
4) 293 292.8, but you can't have 0.8 fleas, so 293
r*N 0.1 * 200 = 20 so 220 then week 2 0.1*220=22 so 242 then week 3 0.1*242=24.2 so 266.2
then week 4 0.1*266.2 = 26.6 so 292.8
Solutions to Problem Set 2
1) birth rate = 0.048 ; death rate = 0.04
birth rate= 12000/250000 and death rate = 10000/250000
2) 0.008 ; growing
growth rate = birth rate - death rate so 0.048 - 0.04
3) birth rate = 0.047 and death rate = 0.048
birth rate = 109000/2300000 and death rate = 111000/2300000
4) growth rate = -0.001 ; shrinking
growth rate = birth rate - death rate so 0.047 - 0.048
5) growth rate = 0.01
birth rate = 30/1500 and death rate = 15/1500 so
birth rate = 0.02 and death rate = 0.01
growth rate = birth rate - death rate
6) population = 227700
population growth = r * N so -0.001 * 2300000 = -2300
Population equals initial population + growth so 2300000 + (-2300)
7) Population after 3 years = 256047
after one year 0.008 * 250000 = 2000 growth so population after 1 year is 252000
after two years 0.008 * 252000 = 2016 growth so population after 2 years is 254016
after three years 0.008 * 254016 = 2032 growth so population after 3 years is 256048
