Exponential Growth

Exponential Growth

Growth Example 1

A colony of bacteria has a population of three thousand at noon on Sunday. During the next week, the colony's population doubles every day. What is the population of the bacteria colony at noon on Saturday?

Step 1. Determine the initial value.

Since the first day recorded is Sunday, the initial population is 3,000.

Step 2. Determine the growth factor.

Since the population is doubling, it is being multiplied by 2 each day. Therefore, the growth factor is 2.

Step 3. Write an exponential function.

The general form of an exponential function is ExpGrowthEx1-1.

This function is ExpGrowthEx1-2.

Step 4. Use the equation to solve the problem.

Since Saturday is 6 days after the initial day, Sunday, we will use x = 6.

ExpGrowthEx1-3

y = 192,000 bacteria