Răspuns :
x-pretul initial
x-15/100*x=17
85x/100=17
85x=1700
x=20
x-15/100*x=17
85x/100=17
85x=1700
x=20
x - 15%x = 17
x - 15·x/100 = 17
(100x - 15x)/100 = 17
85x/100 = 17
85x = 1700
x = 20
x - 15·x/100 = 17
(100x - 15x)/100 = 17
85x/100 = 17
85x = 1700
x = 20