Unknown Exponents

In a lab, a colony of 100 bacteria is placed on a petri dish. The population triples every hour. How many bacteria will there be after 3 hours? Check all that apply.

• 900

• 2700

• 8100

How would you estimate or find the population of bacteria in 4 hours? Check all that apply.

• By measuring the initial population and using the growth rate formula

• By observing under a microscope

• By counting manually

• Multiply 100 by 3 four times. Or, find 100⋅3⁴

How would you estimate or find the population of bacteria in 90 minutes?

• By measuring the initial population and using the growth rate formula

• By counting each bacterium individually

• By assuming the population doubles every 90 minutes

How would you estimate or find the population of bacteria in 1/2 hour?

• By measuring the initial population and using the growth rate formula

• By observing under a microscope

• By counting each bacterium manually

A $1,000 investment increases in value by 5% each year. About how many years does it take for the value of the investment to double?

• 14 years

• 15 years

• 16 years

• 17 years

Exponential Growth occurs when-

• populations have plenty of food/space

• home to keystone species

• have few evasive species in a habitat

• have little to no competition or predators

Population growth that is not limited

• Exponential

• Logistical

• Multiplication

• Linear

What does the graph represent?

• Emigration
• Exponential growth
• Immigration
• Logistic Growth

Where on the graph does the population experience exponential growth?

• A to B

• B to C

• A to C

On the day a video was posted online, 5 people watched the video. The next day the number of viewers had doubled. Assume the number of viewers continues to double each day. On which day will 640 people see the video?

• 5

• 7

• 9

• 4