简便计算61.37-9.64+2.45=61.37+2.45-9.64=63.82-9.64=54.18
脱式计算61.37-9.64+2.45=61.37+2.45-9.64=63.82-9.64=54.18
原式=61.37-10+0.36+2.45=51.37+2.81=54.18
