Question

vreau si eu problema asta...dau 25 puncte si coroana

Answer 1

A- 20/ 100× 2A =567
A -2/5xA=567
5A-2A=2835
3A=2835
A=945lei
R:945 lei

Answer 2

Z-prețul final,z=567
y-prețul după prima ieftinire
x-prețul inițial
y=x-10%din x= x-10%•x= x-10/100•x=x-1•x/10=x-x/10
z=y-10%•y=y-10y/100=y-y/10
567=y-y/10
10y/10-y/10=567
9y/10=567
9y=567•10
y=5670:9
y=630
x-x/10=630
10x/10-x/10=630
9x/10=630
9x=630•10
9x=6300
x=6300:9
x=700 lei.