The time taken to double the population is 58 years.
What is exponential growth?
An exponential growth problem is one for which we define the model; P= Poe^rt
Where;
P = population at time t
Po = initial population
r = population growth rate
t = time taken
1800000 = 900,000e^(0.012 × t)
1800000/900,000 = e^(0.012 × t)
2 = e^(0.012 × t)
ln2 = 0.012 × t
t = ln2/0.012
t = 58 years
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