x+4/100orix=x+4x/100 aducem la ac numitor amplficand cu 100 rezulta 100x/100+4x/100=104x/100 simplificam cu 4 =26x/25 pretul dp scumpire 26x/25-5/100 ori 26x/25=123,5 aducem la ac numitor 2500 si rezulta 2600x/2500-130x/2500=308750/2500 2470x=308750 x=125