Explanation: I started with 30 then reversed everything so I subtracted 10, multiplied by 4, and then added 6, and got the number 86. Then I checked the answer by subtracting 6 from 86, then divided it by 4, added it to 10, and the final number equaled 30.
I hope this is the answer you were looking for! I’m so sorry if it’s wrong!
when solving sales tax it's pretty simple because all you do is add everything for a subtotal and multiply your sub total by the tax so i'll use the first as an example your subtotal is 19.96 x0.05 to get 0.99 <-- your sales tax and your final total with tax to be 20.96