Răspuns :

Slavitescudoraid

x1 = x+10/100x = x + 1/10x = 10/10x +1/10x = 11/10x  pretl dupa scumpire

x2 = x1-10/100x1 =  11/10x -1/10x*11/10x = 11/10x- 11/100x = 110/100x - 11/100x = 99/100x pretul dupa ieftire

dar x2 = 1980

99/100x = 1980

99x = 198000

x =198000/99

x =2000 lei costa pretul initial

Răspuns:

110% la scunpire ,  90% la ieftinire ;   x pretul ;    110/100*X*90/100=1980 ;                          99 X/100=1980 ;    X=1980*100/99=2000

Explicație pas cu pas:

ID Alte intrebari