Writing and interpreting functions

Jerome rides at a constant speed of 15 ft/s. Write an equation that expresses the distance, d, that Jerome has traveled as a function of the time, s in seconds.

• d = 15s

• d = 10s

• s = 15d

• s = 10d

A person can encode 1000 words in every hour of typing job. Which of the following expresses the total words W as a function of the number n of hours that the person can encode?

• 𝑊(𝑛)=1000+𝑛

• 𝑊(𝑛)=1000/𝑛

• 𝑊(𝑛)=1000𝑛

• 𝑊(𝑛)=1000−𝑛

Sonya has $40 in her lunch account and pays $2 each day to eat lunch. Which equation can be used to find the amount of money Sonya has left on her account after x days?

• f(x) = 40 + 2x

• f(x) = 40 - 2x

• f(x) = 2 + 40x

• f(x) = 2 - 40x

Write a function for the following statement.

Lin is tracking the progress of her plant's growth. Today the plant is 5 cm tall. The plant grows 1.5 cm per day.

•  $f\left(x\right)=5x+1.5$ 

•  $f\left(x\right)=1.5x+5$ 

•  $f\left(x\right)=5\left(1.5\right)^x$ 

•  $f\left(x\right)=1.5\left(5\right)^x$ 

Tickets to a basketball game can be ordered online for a set price per ticket plus a $5.50 service fee. The total cost in dollars for ordering 5 tickets is $108.00. Which linear function represents c, the total cost, when x tickets are ordered?

• c(x) = 5.50 + 20.50x

• c(x) = 5.50x + 20.50

An architect is designing an office building with n floors that will have an FM radio antenna 15.85 meters tall on its roof. Each floor of the building will be 3.9 meters high. Which function can be used to find the total height of the building in meters, including the FM antenna?

• h(n) = 15.85n + 3.9

• h(n) = 3.9n + 15.85

• h(n) = 3.9n - 15.85

• h(n) = 19.75n

Lee charges $3 for a basket and $2.50 for each pound of fruit picked at the orchard. Write a function f(x) for the total cost of x pounds of fruit from the orchard.

• f(x) = 3x + 2.5

• f(x) = 2.50x + 3

• f(x) = 2.50x

• f(x) = 3x + 2.50

A company has a monthly budget of x dollars. Every month, $30, 400 of the monthly budget is spent on salaries. One-eighth of the remaining budget is spent on office supplies. Which function can be used to calculate the amount, in dollars, spent on office supplies?

• f(x) = (x - 30400) * 8

The local service center advertises that it charges a flat fee of $50 plus $8 per mile to tow a vehicle. Write an equation that represents the total cost (C) of a service for m miles of towing.

• y=8x+50

• y=50x+8

• C=50m+8

• C=8m+50

A real estate agent earns a base salary of $1250.  For every house, h, she sells, she receives $750.  
Which equation could be used to determine the amount of money, m, she would have after selling any number of houses, h?

• m = 1250 + 750h
• m = 750 + 1250h
• 1250 = 750h + m
• 750 = 1250m + h