Since the saved money is 200 pesos and the hard drive is marked 5%, then we can say that 200 is the 5% of the actual amount.
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Let 'c' be the price without the discount
5%c = 200
converting 5% to decimal you'll have:
0.05c = 200
dividing the whole equation by 0.05
0.05c = 200
c = 200/0.05
c = 4,000
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Therefore the actual price is 4,000
