Question

The world population at the beginning of 1980 was 4.5 billion. Assuming the population continued to grow at the rate of approximately 1.3% per year, find a function Q(t) giving the population of the world (in billions) as a function of time t (in years)

Answer 1

The function Q(t) = 4.5 billion (1.013)^t will give the population in t years

Explanation:

Here, we want to write a function

The growth percentage is 1.3% = 1.3/100 = 0.013

The function Q(t) will be an exponential function and it will be represented as;

Q(t) = I ( 1 + r)^t

where I is the initial world population at 1980 = 4.5 billion

r is the growth percentage = 1.3% = 0.013

t is the time in years

Substituting these values, we have;

Q(t) = 4.5 billion (1 + 0.013)^t

Q(t) = 4.5 billion (1.013)^t