The percent off the store should display is 27.0%
The percent off the store should display is the total percent off given to their product. That is, the addition of the first and second percent off.
The total percent off the store gave to Matt is calculated as;
= 20% + 7%
= 27%
To the nearest tenth of a percent = 27.0%
Thus, the percent off the store should display is 27.0%
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