Answer:
25% is the answer.,....
money Alicia save= 28-21= 7
percentage Alicia saves with the sale= 7/28*100
= 25%
All answers are the pic.
When you are lining up the ratios, make sure they are aligning each other with the same unit.

solve for "K", to see what "K" is, or the "constant of variation",
once you found K, plug it back in y=Kx, and that's the equation
1/10,000
Hope i helped
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