45.9+5.17-(13.98+1.17)=45.9+5.17-13.98-1.17=45.9-14+0.02+(5.17-1.17)=34.9+0.02+4=38.92望采纳,谢谢
45.9+5.17-(13.98+1.17)=45.9+5.17-13.98-1.17=45.9+(5.17-1.17)-13.98=45.9+4-13.98=35.92
45.9+5.17-13.98-1.17=45.9-13.98+5.17-1.17=31.92+4=35.92