Appropriate Domain and Range

The function f(x) = 1,575 – 225x models the value of a computer x years after it was purchased. What is an appropriate domain for this function?

• x ≥ 0

•  x ≤ 7

• x ≥ 7

• 0 ≤ x ≤ 7

Sarah’s car holds a maximum of 12 gallons of gas. The function f(g)=3.50g models the relationship between the total cost of gas, f(g), and the number of gallons of gas purchased, g. What is the most appropriate domain of the function?

• all positive integer values of x 

•  all positive real values of x

•  0 < g < 12   where g is an integer

• 0 < g < 12    where g is a real number

Amy has a $40 gift card to Wal-Mart. She does not have any additional money to spend. She will purchase an i-phone charger for $12 and x number of gifts for her friends that are $6 each. 

The function f(x)= 28 -6x  models the balance on the gift card after her purchases. What is the appropriate domain.

•  all integer values of x

• all positive integer values of x

• 0 < x < 4 where x is a whole number

• 0 < x < 4

The function p(h) = 2h -15 represents the profit a company makes selling h hot dogs. Which is the most appropriate domain of the function?

• all positive integers

•  all positive real numbers

• all positive integers greater than 15

• all positive real numbers greater than 15

Which domain would be the most appropriate to use for a function that compares the number of emails sent (x) to the amount of data used for a cell phone plan (y)?

• Integers

• Whole Numbers

• Rational Numbers

• Irrational Numbers

A store sells self-serve frozen yogurt sundaes. The function C(w) = 1.5w represents the cost, in dollars, of a sundae weighing w ounces. An appropriate domain for the function would be which of the following?

B\left(x\right)=2^x represents the number of bacteria, B(x), after "x" hours. What is an appropriate domain?

• All Real Numbers

• All Integers

• Positive integers

• Positive rational numbers

• { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }
• { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }
• y ≤ 10
• 0 ≤ y ≤ 10

Q1. What types of numbers are included?

• A) All integers

• B) All real numbers

• C) Non-negative integers

• D) Non-negative real numbers

Hector’s service club is raising money by wrapping presents in the mall. The function f(x) = 3x describes the amount of money, in dollars, the club will earn for wrapping x presents. They only have enough wrapping paper to wrap 1000 presents. What is an appropriate domain?

• 1000≤x≤0

• x≥1000

• 0≤x≤1000

• x≤3000