设乙数为x
12.5%x+2=30
x=224
乙数x
30-2=12.5%x
1/8x=28
x=28x8
x=224
设乙数为X,依题意得:12.5%X+2=30
12.5%X=30-2
12.5%X=28
X=28/12.5%
X=224