Tina has a pet sitting business. She charges a flat service fee of $30, plus $15 per day for each animal. If one of her customers spent less than $75 on one animal, which of the following inequalities could be used to solve for x, the number of days the customer paid for pet sitting?
A.
$15x - $30 < $105
B.
$15x + $30 < $75
C.
$15x < $75
D.
$15x < $105