题目

如果a＝b（a、b均不为0），那么a∶b＝（________）。 答案：【答案】5∶6【解析】表示两个比相等的式子叫做比例；在比例中，两个外项的积等于两个内项的积，这叫做比例的基本性质。因为a＝b，结合分析及题意，可把含有a的因式看作外项，含有b的因式看作内项，得到：。Robeson was born in a very poor family.At seven,he had to pick coal in a deserted mine near his home,then he sold   26   he had picked and earned a few coins to help his parents.He had   27  schooling,for being so poor,how could they   28   school fees? When he was fifteen,he worked   29   a servant in a school.Looking at other children studying in the classroom,he felt   30  for himself.How he   31   to have the same chance!He decided to study by   32   .In the daytime,after the sweeping and cleaning was over,he   33   stand by the window outside the classroom trying to catch what the teacher said.At night,he tried his best to remember what he   34  during the day.He worked   35   hard at his lessons that he sometimes had just three or four hours to sleep.The more he learned,the greater   36   he showed in his lessons.A maths teacher discovered him and came to like this diligent boy and   37  him to sit at the back of the class.In one exam,he was the   38  one in the whole school who reached the highest grade.He would have been given the scholarship if he   39   a regular student of the school. Robeson   40  rough six long years with his study of maths and wrote several articles which captured the   41  of some university professors.They admired his talent   42   his diligence.To give him a good chance,they hired him as a librarian and   43   him free guidance.Robeson felt  44  ,for he was sure that before him there was a broad road   45   success. 26.A.whether                B.which                       C.that                           D.what 27.A.many                   B.few                           C.little                         D.much 28.A.buy                      B.afford                       C.send                          D.read 29.A.as                        B.like                           C.for                            D.by 30.A.angry                   B.ashamed                    C.proud                        D.sorry 31.A.hated                    B.decided                     C.wished                      D.regretted 32.A.the teacher            B.himself                            C.his parents                 D.his schoolmates 33.A.could                   B.ought to                    C.should                       D.would 34.A.had learned                                              B.has been taught C.has heard                                                      D.had been written down 35.A.very                            B.so                             C.too                           D.quite 36.A.joy                       B.interest                      C.time                          D.taste 37.A.allowed                B.agreed                       C.let                                   D.refused 38.A.worst                   B.only                          C.last                           D.laziest 39.A.had been               B.has been                    C.is                              D.was 40.A.learned                 B.listened                     C.mastered                   D.struggled 41.A.notice                   B.influence                   C.eyes                          D.attention 42.A.except for             B.according to                     C.as well as                  D.in spite of 43.A.taught                  B.offered                      C.lent                           D.sent 44.A.sad                       B.angry                        C.happy                       D.disappointed 45.A.leading to             B.coming from             C.made of                    D.covered with