1.(25+15)÷(1-3/4)=160吨
(160+20)÷(1-2/5)=300吨
(300+15)÷(1-1/4)=420吨
2.设最后乙有2份甲有5份 2/(1-3/5)=5
7-5=2
2÷(1-1/3)=3
1+3=4
3/÷4=3/4
1.(25+15)÷(1-3/4)=160吨
(160+20)÷(1-2/5)=300吨
(300+15)÷(1-1/4)=420吨
2.设最后乙有2份甲有5份 2/(1-3/5)=5
7-5=2
2÷(1-1/3)=3
1+3=4
3/÷4=3/4