The population of Upper Anchora was 1,000,000 at the start of 1996 and was doubling every 9 years. How fast was it growing per year at the start of 1996 ?
Round your answer to the nearest thousand.

A)154,000 people per year
B) 78,000 people per year
C) 77,000 people per year
D) 76,000 people per year
E) 67,000 people per year

Question

The population of Upper Anchora was 1,000,000 at the start of 1996 and was doubling every 9 years. How fast was it growing per year at the start of 1996  ?
Round your answer to the nearest thousand.
 
A)154,000 people per year
B) 78,000 people per year
C) 77,000 people per year
D) 76,000 people per year
E) 67,000 people per year

Quizplus · Accepted Answer

To find the annual growth rate, we need to first find the doubling time. We know that the population doubles every 9 years, so we can use the formula:

doubling time = ln(2) / (growth rate)

where ln(2) is the natural log of 2 (about 0.693). Solving for growth rate, we get:

growth rate = ln(2) / (doubling time)

growth rate = 0.693 / 9

growth rate = 0.077 per year

So the population was growing at a rate of 7.7% per year at the start of 1996. To find how many people that represents, we can multiply the growth rate by the population:

annual growth = 0.077 * 1,000,000

annual growth = 77,000

Rounding to the nearest thousand, we get:

Answer: C) 77,000 people per year.

The Population of Upper Anchora Was 1,000,000 at the Start