Using the percentage concept, the percentage of the regular price is 27.5%
Given tha Parameters :
Let the percentage discount = p
We can create an expression thus :
21.75 = (p/100) × 30
21.75 = 0.01p × 30
0.725 = 0.01p
p = 0.725 / 0.01
p = 72.5
Hence, the percentage of the regular price is (1000% - 72.5%) = 27.5%
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