4.5×(1+20%)=5.49÷(1+50%)=6(5.4)比4.5吨多20%9比(6)多50%
4.5x(1+20%)=5.49÷(1+50%)=65.4吨比4.5吨多20%,9比6多50%
5.4, 6
(5,4)吨比4,5吨多20%:9比(6,75)多50%
(5.4)比4.5吨多20%:9比(6)多50%