设乙为X30-12.5%X=2解得X=224
设乙数为x，则依题意有30-12.5%*x=2所以12.5%*x=28解得x=224答：乙数为224
设乙数为X ，甲数为Y12.5% 乘以 X+2 =Y 12.5% 乘以 X = 30-2 X = 28 除以 12.5% X = 3.5
乙数是x。30-12.5%x＝2
