Exponential Growth/Decay

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

• y=5000(0.7)^x
• y=30(5000)^x
• y=5000(1.3)^x
• y=5000x^x

What is the balance of $6000 compounded annually at a rate of 4% for 10 years?

• $8,881.47
• $7,432.93
• $8,400
• $6,500

Jame's 70 in. giant peach doubles in size every week. Write an expression that would represent how big the peach is after 5 weeks.

• 70(2)³⁵
• 70(2)⁵
• 2(70)⁵
• 5(70)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. How many mosquitoes will there be after 4 months?

• 9766
• 9006
• 9765
• 5433

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

What type of function is y = 7(5/4)^x?

• Exponential Growth
• Exponential Decay
• Linear
• None of the above

What type of function is f(x)=2(1/7)^x ?

• Exponential Growth
• Linear
• Exponential Decay
• None of the Abovee

What is 7.25% converted to a decimal?

• .725
• 0.725
• 0.0725
• 7.25

25% as a decimal:  

• 0.25
• 02.5
• 25
• 2500

2% as a decimal:

• 0.02
• 0.2
• 2
• 20