                                           

                                                                                -                                                    

           A'B'      M         A        B             A'B'M ABM          A'B'             BM/B'M=AB/A'B'  B'M       A'B'         AB               0.75    BM    

    A'B'=60  B'M     60     A B  14          BM=AB*B'M/A'B'=14*60/6=140 =105   

                                        AB            B'M/A'B' 10    