Question

O camasa si o cravata costa impreuna 180 lei.daca pretul camasii s'ar mari cu 10%  si cel al cravatel s'ar reduce cu 5% atunci cele 2 obiecte ar costa 186 lei.aflati pretul fiecarui obiect.
Multumesc !

Answer 1

x+y=180  x=180-y
x+10/100*x + y-5/100*y=186
x+x/10+y-y/20=186
(x+y)+x/10-y/20=186
180+x/10-y/20=186
x/10-y/20=6
180-y supra 10 -y/20=6 aducem la acelasi numitor
360-2y-y=120
-3y=120-360
-3y=-240
3y=240
y=80  x=100