被减数=减数+差所以:被减数=三数和/2=0.54/2=0.27
x-y=zx+y+z=x+y+x-y=2x=0.54x=0.27
被减数是0.27。被减数设为X,减数为Y,差为Z,则有:X-Y=Z(1) X+Y+Z=0.54(2) (1)+(2)可推出X为0.27
当然是0.27咯
0.27