设东东是x,圆圆是y,毛毛是(57-y)
x+y=52 y=52-x
x+(57-y)=55 x-y=-2
x-(52-x)=-2
x-52+x=-2
2x=50
x=25
y=52-25=27
毛毛 57-y=57-27=30