First, you have to apply the sale to the original price. In this case, you would have to multiply 22 and 43% to get $9.46. Now, you have to subtract 9.46 from 22 to get 12.54.
-5/8 divided by -3/4 is the same as -5/8 multiplied by -4/3. Multiply the tops to get 20. Multiply the bottoms to get 24. A negative over a negative is positive and you end up with 20/24! :)
