jaskiransohi1
contestada

The population of a city is growing at an average rate
of 3% per year. In 1990, the population was 45 000.
a) Write an equation that models the growth of the
city. Explain what each part of the equation
represents.
b) Use your equation to determine the population
of the city in 2007.
c) Determine the year during which the population
will have doubled.
d) Suppose the population took only 10 years to
double. What growth rate would be required for
this to have happened?

Respuesta :

kelly3101
 a. N(y) = 45,000*1.03^(y-1990) 
N(y) = population in year y, 
45,000 = poppulation in 1990, 
1.03 = yearly growth factor, 
y = year y 

c. 90,000 = 45,000*1.03(y-1990) 
2 =1.03^(y-1990) 
(y-1990)*log 1.03 = log 2 
(y-1990) = log 2 / log 1.03 = 23.45 
y = 2013.45 
ans: middle of 2013