A1 Warm-Up 9.4 Practice Day - Exponential Growth & Decay

Suppose a culture of bacteria begins with 5000 cells and decreases by 30% each year. Write an equation that represents this situation.

• y=5000(0.7)^x
• y=5000(0.3)^x

• y=5000(1.3)^x
• y=5000(30)^x

Tags

CCSS.HSF.LE.A.2

The number of mosquitoes at the beginning of the summer was 4,000. The population of mosquitoes is expected to grow at a rate of 25% a month. Which equation represents the rate of population growth?

• y=4000(0.75)^x

• y=0.25(4000)^x

• y=4000(0.25)^x

• y=4000(1.25)^x

Tags

CCSS.HSF.LE.A.2

Write an equation that models the following situation:
Samantha's hair was known to grow very rapidly. It began at a length of 6 in and grew at a rate of 14% a week.

• y=6(0.14)^x
• y=6(1+14)^x
• y=6(1.14)^x
• y=6(0.86)^x

Tags

CCSS.HSF.LE.A.2

What is the percentage rate of growth or decay for the function? y= 6(0.85)^x

• 0.85%

• 15%

• 85%

• 0.15%

Tags

CCSS.HSF-IF.C.8B

What is the percentage rate of growth or decay for the function? y= 6(0.62)^x

• 0.38%

• 38%

• 62%

• 0.62%

Tags

CCSS.HSF-IF.C.8B

Which of the following functions shows an initial amount of $15 and an increase of 35% each year?

• y = 15(35)^x
• y = 15(1.35)^x
• y = 15(0.35)^x
• y = 35(1.15)^x

Tags

CCSS.HSF.LE.A.2

What is the percentage rate of growth or decay for the function? y= 6(1.24)^x

• 0.24%

• 124%

• 24%

• 2.4%

Tags

CCSS.HSF-IF.C.8B

Daniel’s Print Shop purchased a new printer for $35,000. Each year it depreciates at a rate of 5%. Which equation represents the value of the printer over time?

• y = 35000(0.95)^x

• y = 35000(1.95)^x

• y = 35000(1.05)^x

• y = 35000(0.05)^x

Tags

CCSS.HSF.LE.A.2

The attendance at the art museum at the New Year’s opening was 250 people. The attendance has been increasing at a rate of 3% each month. Which equation represents the growth of the population each month?

• y = 250(1.03)^x

• y = 250(1.3)^x

• y = 250(0.97)^x

• y = 250(0.03)^x

Tags

CCSS.HSF.LE.A.2

Since January 1980, the population of the city of Brownville has grown according to the mathematical model y=720,500(1.022)^x, where x is the number of years since January 1980. What is the percentage increase of the population annually?

• .022%

• 102.2%
• 2.2%
• 22%

Tags

CCSS.HSF-IF.C.8B