Jason likes to play video games. His parents allow him to play for 20 min plus 10
min for each half hour he does chores or studies. He can never play for more
than 90 min/day.
The function f(x)=20+10x models the number of minutes per day Jason could
play where x represents the number of half hour increments he has done chores
or studied.
What is the practical range of the function?
A. all multiples of 10 greater than or equal to 20 and less than or equal to 90
B. all integers
C. all real numbers greater than or equal to 20
D. all real numbers