20480 : ( 380 + х : 2 ) = 1536 : 48

20480/(380+Х/2)=32                                                                                                       (380+Х/2)=20480/32                                                                                                    (380+Х/2)=640                                                                                                                Х/2=640-380                                                                                                                  Х/2=260                                                                                                                           Х=260*2                                                                                                                            Х=520                                                                                                                             20480/(380+520/2)=1536/48                                                                                           32=32