(0.4x+6.9)/0.5-(0.02x+0.03)/0.03=(x-5)/2
12(0.4x+6.9)-200(0.02x+0.03)=3(x-5)
4.8x+82.8-4x-6=3x-15
0.8x+76.8=3x-15
2.2x=91.8
x=459/11