3.1-3.2 Review

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

• 300
• 1.16
• .16
• x

Which of the following functions shows an initial amount of $75 and a decrease of 12% each year?

• y = 75(12)^x

• y = 75(1 + 0.12)^x

• y = 75(0.88)^x

• y = 75(88)^x

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+ 0.14)^x

• y=6(1 - 0.14)^x

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

• y=5000(1 - 0.30)^x

• y=30(5000)^x

• y=5000(1 + 0.30)^x

• y=5000x^x

Change 6.75% to a decimal.

• 67.5
• .675
• 675
• .0675

Change 11.2% to a decimal.

• 11.2

• 1.12

• 0.112

• 0.0112

What is the decay rate in the following model?
A=1200(.85)⁶

• 1200

• 0.15

• 0.85

• 6

Give the rate of decay:
y = 35(0.65)^x

• 35%
• 65%
• 0.35%

• 165%

Give the rate of growth:
y = 5(1.27)^x

• 127%
• 27%
• 5

Which of the following is an exponential function?

• y = x²

• f(x) = 3x³

• y = x³

• f(x) = 3^x