Explanation:
don't guess around, just calculate yourself.
first he sold a car for $15,075.
c(15075) = 250 + 0.02×15075 = $551.50
then he sold another car for $21,640.
c(21640) = 250 + 0.02×21640 = $682.80
his total commission was
$551.50 + $682.80 = $1,234.30
c(p) = 745.80
what was p ?
745.8 = 250 + 0.02p
495.8 = 0.02p
p = 495.8/0.02 = $24,790