+ = | 0.8+4.2= | +3= | - = | 1.2- = | - = |
1- = | 7.7+ = | -2= | 5- = | - = | + = |
解: + = , | 0.8+4.2=5, | +3=3 , | - = , | 1.2- =1, | - = , |
1- = , | 7.7+ =8, | -2= , | 5- =4 , | - = , | + = . |
分析:异分母分数相加减,先通分,变成同分母分数,再根据同分母分数相加减,分母不变,分子相加减的方法求解.
点评:本题主要考查了异分母分数加减法,计算时要细心,把结果化成最简分数.
编辑:chaxungu时间:2026-04-27 10:41:56分类:小学数学题库
+ = | 0.8+4.2= | +3= | - = | 1.2- = | - = |
1- = | 7.7+ = | -2= | 5- = | - = | + = |
解: + = , | 0.8+4.2=5, | +3=3 , | - = , | 1.2- =1, | - = , |
1- = , | 7.7+ =8, | -2= , | 5- =4 , | - = , | + = . |