Question

14．算一算
$\frac{1}{4}$×35+65÷4                          （$\frac{1}{5}$-$\frac{1}{6}$）×6×5
236÷$\frac{5}{9}$+236÷$\frac{5}{41}$                        $\frac{71}{258}$×259．

Answer 1

分析 （1）、（2）、（3）、（4）根據(jù)乘法分配律進行簡算．

解答 解：（1）$\frac{1}{4}$×35+65÷4
=$\frac{1}{4}$×35+65×$\frac{1}{4}$
=$\frac{1}{4}$×（35+65）
=$\frac{1}{4}$×100
=25；

（2）（$\frac{1}{5}$-$\frac{1}{6}$）×6×5
=$\frac{1}{5}$×6×5-$\frac{1}{6}$×6×5
=6-5
=1；

（3）236÷$\frac{5}{9}$+236÷$\frac{5}{41}$
=236×$\frac{9}{5}$+236×$\frac{41}{5}$
=236×（$\frac{9}{5}$+$\frac{41}{5}$）
=236×10
=2360；

（4）$\frac{71}{258}$×259
=$\frac{71}{258}$×（258+1）
=$\frac{71}{258}$×258+$\frac{71}{258}$×1
=71+$\frac{71}{258}$
=71$\frac{71}{258}$．

點評 考查了運算定律與簡便運算，四則混合運算．注意運算順序和運算法則，靈活運用所學的運算定律簡便計算．