Identifying and Evaluating Exponential Functions

Identify the y-intercept (initial value) in the function f(x)=13(.27)^x

• (.27)^x
• .27
• 13
• 3.51

Identify the common ratio (multiplier) of the function f(x)=2(4)^x.

• 2
• 4
• (2)^x
• 8

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

• Growth
• Decay
• Linear
• None

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

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

Is the equation linear, exponential or neither?

• Linear
• Exponential
• Neither

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

The half-life of Zn-71 is 2.4 minutes. If one had 100.0 g at the beginning, how many grams would be left after 7.2 minutes has elapsed?  

• 11.5 grams
• 12.5 grams
• 13.5 grams
• 14.5 grams

What is the balance of a $4500 bond that earns 6.5% interest when compounded annually after 3 years?

• $5435.77
• $5400
• $5377.50
• $5300

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

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

• 6%
• 8,000
• 0.6
• 0.06