92,4 lei.............90% 100% - 10% = 90%
x ................. 100%
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x =( 92,4 · 100 ): 90 = 102,6 lei pret intermediar
102,6...............92% 100% - 8% = 92%
x ......................100%
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x = (102 · 100) : 92 = 23000 : 92 = 110, 86 lei pret initial