Baus Exponential Functions 2

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

Which of the following ordered pairs is on the graph of f(x) = 3(5)^x ?

• (3, 375)

• (4, 1870)

• (2, 70)

• (1, 8)

James' 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

Identify each function as representing exponential growth or decay and determine the rate.
f(x) = 4(0.89)^x

• growth; 11%

• decay; 11%

• growth; 89%

• decay; 89%

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?

• 9765

• 15

• 1265

• 976

Classify the model as Exponential GROWTH or DECAY.
f(x) = 10(1.01)^x

• Growth

• Decay

• Neither

• Cannot Determine

Which of the following functions models exponential growth?

• f(x) = 4(1.78)^x

• f(x) = -2(0.45)^x

• f(x) = 7(½)^x

• f(x) = 2(-4.3)^x

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

• y=8(15,000)^x

• y=15,000(1.08)^x

• y=15,000(0.92)^x

• y=15,000(0.08)^x

Write an exponential function that models the following situation:  A new car you bought for $38,000 decreases in value 11% each year.

• f(x) = 38000(0.89)^x

• f(x) = 0.89(38000)^x

• f(x) = 38000(1.11)^x

• f(x) = 38000(0.11)^x

Classify the model as Exponential GROWTH or DECAY.
f(x) = 1200(.85)^x

• Growth

• Decay

• Cannot Determine

• Neither