Question

The growth of the world's population can be represented as A = Aoert, where A is the population at time t, Ao is the

population at t = 0, and r is the annual growth rate. The world's population at the beginning of 2008 was estimated at 6,641,000,000. If
the annual growth rate is 1.2%, in what year will the world population reach 9 billion?

Answer 1

We can use the given population growth formula:

A = Ao * e^(r*t)

Let's first find out what the value of t is when the population reaches 9 billion:

9,000,000,000 = 6,641,000,000 * e^(0.012*t)

Dividing both sides by 6,641,000,000, we get:

1.355 = e^(0.012*t)

Taking the natural logarithm of both sides, we get:

ln(1.355) = 0.012*t

Solving for t, we get:

t = ln(1.355) / 0.012 ≈ 41.8

the world population will reach 9 billion in the year 2050 (2008 + 41.8).

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