M+2x=M+3x/2+2/7(M+3x/2)
2x=3x/2+2M/7+3x/7
2x=27x/14+2M/7
2x-27x/14=2M/7
x/14=2M/7
x=4M
Dolu depo 3x olduğundan 3x=12M olur