+ = | 39× = | 1÷ = | × = |
÷4= | ×24= | 4÷10%= | - = |
| 25%+25= | ÷25%= |
解: + = , | 39× =15, | 1÷ = , | × = , |
÷4= , | ×24=18, | 4÷10%=40, | - = , |
| 25%+25=25.25, | ÷25%=1. |
分析:分数加减法:先通分化成同分母的分数,再相加减;
分数乘法:分子相乘的积做分子,分母相乘的积做分母,能约分的先约分;
分数除法:除以一个不为零的数等于乘上这个数的倒数.
点评:本题考查了简单分数计算,计算时要细心,注意把结果化成最简分数.
+
=
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×
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÷4=
×24=
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÷25%=
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