Exponential Growth & Decay WP

In the equation 𝑦 = 2.1 (1.04) 𝑥 , what is the initial value?

• 1.04%

• 2.1

• 1.04

• 2.1 %

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

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

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

• 300
• 1.16
• .16
• x

• 245,000
• increasing
• 12%
• 12,000
• 88%
• 112%
• 630,000
• decreasing

A population of 2200 beetles is too large to sustain and decreases in population each month at a rate of 5%. How would you write your decay factor, b?

• -5
• -.05
• .95
• .05

The value of a car is $15,000 and depreciates at a rate of 8% per year. What is the decay factor?

• ^.08
• ^1.08
• .92
• 8

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