You can
put this solution on YOUR website!9+.23x<20 9 being the pick up fee, x being unknown number of miles, and 20 amount spent.
you will have to add the pickup fee to the cost per mile and set that less than 20. If you had to solve this problem, which as you have it stated you do not, but if you did, treat the < sign like an = sign and solve for x. When you do a equation like this, remember if you sign before the x value is neg. you have to flip your sign to >,