2*（0.8*0.75*2+0.75*0.75）*100=352.5
（0.8*0.75+0.8*0.75+0.75*0.75）*2*100=352.5 *为乘号请采纳吧！谢谢
（0.8×0.75+0.8×0.75+0.75×0.75）×2×100
