用简便方法计算下面各题．
3.06﹣2.5+1.94           3.8+3.98+6.02              9.53﹣（4.53+2.4）
76﹣9.36﹣30.64          2.29+3.7+6.71+6.3          3.25﹣0.13﹣1.25﹣0.87．