（1）原式=8.65-5.36

                =3.29（2）原式=6.5+16.44

                =22.94

（3）原式=19.46-1.964

                =17.496（4）原式=6.43-2.73

                =3.7

（5）原式=87.3-54.1

                =33.2（6）原式=100-60.45

                =39.55