1. 直接写得数。                                                                                                                          

64﹣34＝	28+63＝	820+60＝	77﹣57＝	35+24＝	90﹣37＝
54+45＝	62﹣18＝	66﹣39＝	350﹣60＝	490﹣27＝	710+280＝