Metoda grafica:
Maria |__|
Ioana |__|+20 }240
Cristina |__|__|+40
240-40-20=180
180:4=45 reprezintă un segment
Maria:45 ron
Ioana:45+20=65 ron
Cristina=45×2+40=130 ron
Rezolvare algebrica:
M+I+C=240 ron
I=20+M
C=2×I=2(20+M)=40+2M
M+20+M+40+2M=240
4M==240-60
4M=180
M=180:4
M=45ron
I=20+45=65ron
C=40+2×45=40+90=130