Question

Jason is selling video games. To earn his monthly bonus, he must sell a minimum of 5 games. He has 30 he can sell. The video games cost $20 each. The function f(x) = 20x can be used to represent this situation. What is the practical range of the function?

All whole numbers from 5 to 30, inclusive.


All whole numbers from 100 to 600, inclusive.


All real numbers.


All multiples of 20 between 100 and 600, inclusive.

Answer 1

Correct choice is B

Explanation:

The function
`f(x)=20x` represents the situation, where x is the number of sold video games and f(x) is the total cost of sold games.

Jason must sell a minimum of 5 games, this means that
`x\ge 5.` He has 30 video games he can sell, then
`x\le 30.` Thus, the domain of the function is
`5\le x\le 30.`

The range of the function f(x) is

`20\cdot 5\le f(x)\le 20\cdot 30,\\ \\100\le f(x)\le 600.`