Alright, lets get started.
The base price is given : $ 24990
The dealer pays 76% of the base price means
he pays for base price :
he pays for base price : $ 18992.4
For options, total : 
He pays 88% for options, means
he pays for options : 
he pays for options : $ 2270.4
So, total dealer pays :
destination charges
So, total dealer pays :
$ 21892.8
Hence dealer's cost : $ 21892.8
Price of sticker will be : 
Price of sticker will be : $ 28200
dealer's cost : $ 21892.8
Hope it will help :)