Don M. answered 04/26/19
Tutor
4.9
(89)
Reliable, Knowledgeable and Patient Teacher, Mentor, and Grandpa
Hi Ella!
The difference that Dave made is $1.50, so simply divide the $1.50 by the original price of $4.50 and the rate of increase is .333333333 repeating or rounded off 33% mark-up.
Regards,
Don M.