三个未知数，两个方程，神也解答不出来啊
x+y+Z=50=>1500x+1500y+1500z=750001500x+2100y+2500z=900001000z+600y=150005z+3y=75z=(75-3y)/5y=0,z=15,x=35y=5,z=12,x=33y=10,z=9,x=31y=15,z=6,x=29y=20,z=3,x=27y=25,z=0,x=25
