The mall is having a sale on all shoes. Each pair is $3.50 off the original price. Which expression shows the final price of a pair of shoes? 3.5+x
x- 3.5
3.5x
which is the answer???
and could anybody help me with a few more questions?

Amerchant has coffee worth $60 a pound that she wishes to mix with 50 pounds of coffee worth $90 a pound to get a mixture that she will sell for $70 a pound. how many pounds of the & 60 coffee should be used?

Acoin bank containing only dimes and quarters has 12 more dimes than quarters. the total value of the coins is $11. how many quarters and dimes are in the coin bank?

It took alice 5 5/6 hours to drive to her grandparents' house for . on the way home, she ran into traffic and it took her 7 3/8 hours. how much longer did the return trip take? write your answer as a proper fraction or mixed number in simplest form. the trip home took __hours longer. ?