# Using Logic for Problem Solving

Human population has increased significantly in the past decades. Industrialized countries have less growth compared to developing countries. This graph represents world population between 1750 and projected 2050 in billions.

Graph retrieved from Ecology Communications Group, Inc.

Most species’ population growths have a carrying capacity: the point where population growth stops rising exponentially and grows logarithmically. The graph below is an example of what happens once a population exceeds the carrying capacity. Carrying capacity is an inhibitor to how high the population can grow because carrying capacity is the amount of resources an environment can provide.

The problem is in determining how much more the human population will increase in the next 12 years. A projection is that the world human population will grow to approximately 8 billion in the next decade from 2012.

The method to solve this problem is to use multiplication and graph reading. On the graph from Ecology Communication, we can determine that the world population is about 7 billion in 2012. To calculate the population in the next decade we will have to multiply 7 billion by the population growth rate. According to the Population Reference Bureau, the growth rate is 1.2%. This growth rate is suprising because of how much our population has grown. Back in the 1960’s, the growth rate was 2.1% (Population Reference Bureau). This is because developing countries have large young populations.
Next, to solve for the increase in population, you would use the formula:

0.12 x 7 billion

You would get 840,000,000. When you add how much the population had increased to the current population, you get 7,840,000,000, which can be rounded to 8 billion.

Human population will reach 8b in the next twelve years if it follows the pattern.

Zero population growth (ZPG) is an ideal that has it negatives and positives. On one hand, ZPG means human population growth will reach a state of balance where the number of births will equal the number of deaths and societies can more easily deal with sustainable practices. On the other hand, ZPG has the potential to cause major disruption in economic growth since business in general today relies on continually increased production.

Bibliography:
Algebra Lab. “Biology Graphs: Carrying Capacity.” Algebra Lab. Mainland High
School, n.d. Web. 10 Feb. 2012. practice.aspx?file=Reading_CarryingCapacity.xml>.

McLamb, Eric. “The Day of Seven Billion.” Ecology. Ecology Communications Group,
Inc., 24 Jan. 2012. Web. 10 Feb. 2012. <http://www.ecology.com/2011/09/
26/day-seven-billion/>.

Population Reference Bureau. “Population Projections.” Population Reference
Bureau. N.p., n.d. Web. 10 Feb. 2012. .