eXpo function

An app allows students to submit photos. The graph shows the number of photos p(x) on the app x days after the app goes live.

How many pictures were on the app when the app went live?

• 0

• 3

• 5

• 1

In the school bathroom, a population of 100 bacteria reproduces exponentially. Every hour, each bacteria triples. Write a function in the form of f(t)=ab^t can be used to model the growth of the bacteria population.

what is the value of a?

• 100

• 3

• -100

• -3

1. In the school bathroom, a population of 100 bacteria reproduces exponentially. Every hour, each bacteria triples. Write a function in the form of f(t)=ab^t can be used to model the growth of the bacteria population.

what is the value of b?

• 100

• 3

• -100

• -3

The number of computers on the internet can be shown with the table, can be predicted by the function f(b) = 384(1.045)^b , where b is the number of years since 1982.

What does 384 represent in this context?

• the initial value

• the y intercept

• the x intercept

• the common ratio

• the rate of growth

The value of Mrs. Grimm’s car depreciated each year after she bought it. The function g(t) = 16,098(.89)^t represents the value of Mrs. Grimm’s car t years after she bought it. What is the rate of depreciation?

• .11%

• .89%

• 11%

• 89%

In a research experiment, the population of a colony of bacteria doubles every hour. The population, f(x), of the colony after x hours can be modeled by the function f(x) = 150 (2)^x . What values for the domain are reasonable in the given context?

• all real numbers

• all real number greater than 0

• all real numbers greater or equal to

• all real numbers greater than or equal to 150

The Mason and Delaney families both purchased houses on the same day several years ago.

The Mason family bought their house for $162, 239 and it has been increasing in value by 2.3% each year.

The value of the Delaney family’s home since it was purchased, D(x) can be modeled by the function D(x)= 142,800(1.06)^x. where x represents the number of years since the house was purchased.

Part a: which family paid more for their house?

• Mason

• Delaney

The Mason and Delaney families both purchased houses on the same day several years ago.

The Mason family bought their house for $162, 239 and it has been increasing in value by 2.3% each year.

The value of the Delaney family’s home since it was purchased, D(x) can be modeled by the function D(x)= 142,800(1.06)^x. where x represents the number of years since the house was purchased.

Part b: which family's home is increasing at a faster rate?

• Mason

• Delaney

The growth of collection of Star Wars Toys can be modeled by the exponential function P(t) = 1200 (1.08)^t. The graph models the value of the collection p(t) as a function of the time, t, that has passed.

What was the average rate of change for the first two weeks of population growth?

• 1200

• 8

• 100

• 400

The expression 3280(1.0117)^12t models the future population of sloths in a zoo after t years. Which of the following is the approximate yearly growth rate of the sloth population?

• 0.1%

• 1.17%

• 14.04%

• 14.98%