Exponential Equations Word Problems

The population of Winnemucca, Nevada, can be modeled by P=6191(1.04)^t where t is the number of years since 1990. What was the population in 1990?

• 0 people

• It doesn't say

• 6191 people

• 104 people

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

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

Since January 1980, the population of the city of Brownville has grown according to the mathematical model y=720,500(1.022)^x, where x is the number of years since January 1980. What is the percentage increase of the population annually?

• 720,500%

• 102.2%

• 2.2%

• 22%

What is a, the starting term, for the function: f(x) = 800(0.85)^x?

• 800

• 0.85

• 0.15

• x

The amount of cola in a soda machine decreases (disminuye) by a rate of 5% each hour. The amount of cola in the machine was originally 75 gallons. Which function models the amount of cola in gallons after h hours?

• f(h) = 75(-5)^h

• f(h) = -5(75)^h

• f(h) = .95(75)^h

• f(h) = 75(.95)^h

A particular type of cell triples in number every hour. Which function can be used to find the number of cells present at the end of h hours if there are initially (inicialmente) 6 of these cells?

• f(h) = 3(6)^h

• f(h) = 6x^h

• f(h) = 6(3)^h

• f(h) = 3(6h)

The cost of tuition at a college is $12,000 and is increasing (aumentando) at a rate of 6% per year. Which equations represents this situation?

• C(t) = 1.06(12000)^t

• C(t) = 12000(.06)^t

• C(t) = 12000(.06)^t

• C(t) = 12000(1.06)^t

Write an exponential function to model the situation. The value of a car is $18000 and is depreciating (disminuyendo) at a rate of 12% per year.

• V(t) = .88(18000)^t

• V(t) = .12(18000)^t

• V(t) = 18000(.88)^t

• V(t) = 18000(.12)^t

The equation f(x) = 300(1.06)^x is being used to calculate the amount of money in a savings account. What does the 1.06 represent?

• 6% growth

• 6% decay

• Initial value

• slope