The tires mary wants to buy for her car cost $200 per tire. a store is offering the following deal.
buy a tire and get the 4th tire for 75% off!
mary will buy 4 tires using the deal. a sales tax of 8% will be charged after applying the discount. how much money will mary save by using the deal instead of paying the full price for all 4 tires?and explain your answer

I think the answer is that Mary will save $162 if she uses the deal instead of paying the full price of $864. So what i did was add up four tires with the price of $200 each. Then i took the 8% tax and turned in to a decimal by moving the the decimal point 2 spaces over to the left like this 0.08 . Then i multiplied 0.08 x 800 and got 64 which then means with out the deal she would pay a total of $864.50. Then i add up 4 tires which would equal $800 then  i turned 75% into a decimal by moving the decimal over 2 spots to the left to get 0.75 then i subtracted 0.75 from $200 and got how much Mary would save on the tire which is $150. Then i add $600 for three tires and the $50 for the one tire and got $650 then i multiplied $650 x 0.08 and got $52 in tax and the total with the deal would be $702. So then Mary saves $162. I hope this helps :)