小数加减法义务教育课程标准实验教科书四年级下册9.85元7.40元《爱心树》比《石头汤》贵多少元?两本书一共多少元?9.85+7.40=9.85-7.40=☆☆9.85+7.40=17.25(元)9.85-7.40=2.45(元)7.409.85+17.251-7.409.852.45□□□●□□●□□□●□□●□□□□□●●51836-158●●9.85元7.40元交给售货员20元,应该找回多少元?两本书一共多少元?9.85+7.40=17.25(元)20-17.25=☆☆20-17.25=2017.25-.002.75●●●2.750.39+0.21=5.6-5.48=0.60.12列竖式计算:0.39+0.215.6-5.480.120.600●55.7753.32.47+9.864.265.60-1.760.850.91-先找出错在哪里,再改正。53.32.477.80+9.864.26560-1.760.8591-3.33+0.02=3.33+0.2=3.33+2=3.353.535.33小数加减要注意,相同数位要对齐。先从低位来算起,化简结果别忘记!2﹒815﹒+﹒8797﹒4﹒—﹒623822拓展延伸: