Exponential Growth and Decay Fall 2021

What is a, the initial amount, for the function: f(x) = 300(1.16)^x?

• 300
• 1.16
• .16
• x

Is the pictured graph growth, decay, or linear or none?  

• Exponential Growth
• Exponential Decay
• Linear
• None

Is this exponential growth or decay?

• Growth
• Decay

A population of fish starts at 8,000 and decreases by 6% per year. What is the population of fish after 10 years?

• 14327
• 4309
• 839
• 7680

You buy a new computer for $2100. The computer decreases by 50% annually. How much is it worth after 2 years.

• 225
• 325
• 425
• 525

• -∞ < y < ∞
• y > 0
• -∞ < x < ∞
• x > 0

• F
• G
• H
• J

There were 417 cell phones sold at an electronics store in January. Since then, cell phone sales at this store have increased at a rate of 3.75% per month.

At this rate of growth, which function can be used to determine the monthly cell phone sales x months after January?

• $f(x)=417(1-0.0375)^x$

• $f(x)=417(1-3.75)^x$

• $f(x)=417(1+0.0375)^x$

• $f(x)=417(1+3.75)^x$

An antibiotic is introduced into a colony of 12,000 bacteria during a laboratory experiment. The colony is decreasing by 14.9% per minute.

Which function can be used to model the number of bacteria in the colony after x minutes?

• $f(x)=12000(1+14.9)^x$

• $f(x)=12000(1-14.9)^x$

• $f(x)=12000(1+0.149)^x$

• $f(x)=12000(1-0.149)^x$

A population of 1500 deer decreases by 1.5% per year. At the end of 10 years, there will be approximately 1290 deer in the population.

Which function can be used to determine the number of deer, y, in this population at the end of t years?

• $y=1500(1-0.015)^t$

• $y=1500(0.015)^t$

• $y=1500(1+0.015)^t$

• $y=1500(1.5)^t$