I believe that it is 75%, because if you take 20*.50= 10*.50=5= 75% of your original price. I think..
X=-6 and x=1/3 are both correct values so A and D
Option 2 because in option one 7.5% of $300 is $22.50 so more would be put in if he chose the second option
I'm working on the same thing right now and I'm using every resource in my hands right now to find a solution. I will edit this post when I have more. If you need any more help I have completed the previous activity and most of this one.
EDIT:
Ok so I checked with somebody who is pretty good with math and they said that 5x=5x would be right. Not too sure but that's what I'm putting.
I put EVERYTHING for this assignment in comments down below. Geez all of this for 5 freakin points.