设从B堆中拿到A堆的黑,白子各为x个和y个.500+x=350+y, 150=-x+y.400-y=3(100-x)=300-3x, 100=-3x+y.150-100=(-x+y)-(-3x+y)=2x=50, x=25.y=150+x=175.从B堆中拿到A堆的黑,白子各为25个和175个时,满足题意.
设从B堆中拿到A堆的黑,白子各为x,y个2(350+y)=500+x+350+y4(400-y)=3(100-x+400-y)x=25,y=175