2024-2025年五年級(jí)下冊(cè)張家口市分?jǐn)?shù)的簡(jiǎn)便運(yùn)算期末模擬卷

一、單項(xiàng)選擇題（每題2分，共20分）1.計(jì)算\(\frac{1}{5}+\frac{2}{5}\)結(jié)果是（）A.\(\frac{3}{10}\)B.\(\frac{3}{5}\)C.\(\frac{2}{5}\)2.\(\frac{7}{8}-\frac{3}{8}\)=（）A.\(\frac{4}{8}\)B.\(\frac{1}{2}\)C.\(\frac{3}{8}\)3.與\(\frac{1}{3}+\frac{1}{4}\)計(jì)算結(jié)果相等的是（）A.\(\frac{4}{12}+\frac{3}{12}\)B.\(\frac{1}{12}\)C.\(\frac{7}{12}\)4.\(\frac{5}{6}-\frac{1}{6}\)的結(jié)果化簡(jiǎn)后是（）A.\(\frac{2}{3}\)B.\(\frac{4}{6}\)C.\(\frac{1}{3}\)5.計(jì)算\(\frac{2}{9}+\frac{4}{9}\)，正確結(jié)果是（）A.\(\frac{6}{18}\)B.\(\frac{2}{3}\)C.\(\frac{6}{9}\)6.\(\frac{3}{7}+\frac{2}{7}\)=（）A.\(\frac{5}{7}\)B.\(\frac{5}{14}\)C.\(\frac{1}{7}\)7.計(jì)算\(\frac{4}{5}-\frac{2}{5}\)得（）A.\(\frac{2}{10}\)B.\(\frac{2}{5}\)C.\(\frac{1}{5}\)8.與\(\frac{1}{2}+\frac{1}{6}\)結(jié)果相同的是（）A.\(\frac{3}{6}+\frac{1}{6}\)B.\(\frac{2}{6}\)C.\(\frac{4}{6}\)9.\(\frac{7}{10}-\frac{3}{10}\)化簡(jiǎn)后是（）A.\(\frac{2}{5}\)B.\(\frac{4}{10}\)C.\(\frac{1}{5}\)10.計(jì)算\(\frac{3}{8}+\frac{1}{8}\)等于（）A.\(\frac{4}{8}\)B.\(\frac{1}{2}\)C.\(\frac{3}{8}\)二、多項(xiàng)選擇題（每題2分，共20分）1.以下哪些是分?jǐn)?shù)加法簡(jiǎn)便運(yùn)算方法（）A.湊整B.通分C.交換律D.結(jié)合律2.能簡(jiǎn)便計(jì)算\(\frac{2}{7}+\frac{3}{5}+\frac{5}{7}\)的方法有（）A.\((\frac{2}{7}+\frac{5}{7})+\frac{3}{5}\)B.\(\frac{2}{7}+(\frac{3}{5}+\frac{5}{7})\)C.\(\frac{3}{5}+(\frac{2}{7}+\frac{5}{7})\)D.\(\frac{3}{5}+\frac{2}{7}+\frac{5}{7}\)3.計(jì)算分?jǐn)?shù)減法簡(jiǎn)便運(yùn)算可能用到（）A.去括號(hào)法則B.交換律C.結(jié)合律D.分配律4.下面計(jì)算正確的有（）A.\(\frac{1}{3}+\frac{1}{4}=\frac{4+3}{12}=\frac{7}{12}\)B.\(\frac{5}{6}-\frac{1}{3}=\frac{5-2}{6}=\frac{1}{2}\)C.\(\frac{3}{8}+\frac{1}{4}=\frac{3+2}{8}=\frac{5}{8}\)D.\(\frac{7}{9}-\frac{2}{3}=\frac{7-6}{9}=\frac{1}{9}\)5.運(yùn)用加法交換律可簡(jiǎn)便計(jì)算的式子有（）A.\(\frac{1}{5}+\frac{3}{7}+\frac{4}{5}\)B.\(\frac{2}{9}+\frac{5}{9}+\frac{1}{9}\)C.\(\frac{3}{11}+\frac{7}{11}+\frac{5}{11}\)D.\(\frac{5}{8}+\frac{3}{8}+\frac{1}{4}\)6.分?jǐn)?shù)簡(jiǎn)便運(yùn)算中，常用的湊整分?jǐn)?shù)對(duì)有（）A.\(\frac{1}{2}\)和\(\frac{1}{2}\)B.\(\frac{1}{3}\)和\(\frac{2}{3}\)C.\(\frac{1}{4}\)和\(\frac{3}{4}\)D.\(\frac{1}{5}\)和\(\frac{4}{5}\)7.計(jì)算\(\frac{3}{4}-\frac{1}{6}-\frac{5}{6}\)可采用的簡(jiǎn)便方法是（）A.\(\frac{3}{4}-(\frac{1}{6}+\frac{5}{6})\)B.\((\frac{3}{4}-\frac{1}{6})-\frac{5}{6}\)C.\(\frac{3}{4}-\frac{1}{6}-\frac{5}{6}\)D.\(\frac{3}{4}-(\frac{5}{6}-\frac{1}{6})\)8.下列哪些式子可以用簡(jiǎn)便方法計(jì)算（）A.\(\frac{1}{8}+\frac{3}{8}+\frac{5}{8}\)B.\(\frac{7}{10}-\frac{3}{10}-\frac{1}{10}\)C.\(\frac{2}{9}+\frac{7}{9}-\frac{1}{9}\)D.\(\frac{4}{11}+\frac{5}{11}+\frac{2}{11}\)9.分?jǐn)?shù)簡(jiǎn)便運(yùn)算中，加法結(jié)合律可用于（）A.三個(gè)分?jǐn)?shù)相加B.四個(gè)分?jǐn)?shù)相加C.兩個(gè)分?jǐn)?shù)相加D.多個(gè)分?jǐn)?shù)相加10.計(jì)算\(\frac{5}{9}+\frac{2}{7}+\frac{4}{9}\)可運(yùn)用（）使計(jì)算簡(jiǎn)便A.加法交換律B.加法結(jié)合律C.乘法交換律D.乘法結(jié)合律三、判斷題（每題2分，共20分）1.分?jǐn)?shù)加法交換律和整數(shù)加法交換律意義相同。（）2.計(jì)算\(\frac{2}{3}+\frac{1}{4}\)要先通分再相加。（）3.\(\frac{3}{5}-\frac{1}{5}+\frac{2}{5}=\frac{3-1+2}{5}=\frac{4}{5}\)（）4.簡(jiǎn)便運(yùn)算只能在整數(shù)運(yùn)算中使用，分?jǐn)?shù)運(yùn)算不能用。（）5.計(jì)算\(\frac{7}{8}-\frac{3}{8}-\frac{1}{8}=\frac{7-3-1}{8}=\frac{3}{8}\)（）6.分?jǐn)?shù)運(yùn)算中，加法結(jié)合律和交換律不能同時(shí)使用。（）7.\(\frac{1}{6}+\frac{3}{6}=\frac{1+3}{6}=\frac{2}{3}\)（）8.計(jì)算\(\frac{4}{9}+\frac{5}{9}-\frac{2}{9}\)可以先算加法再算減法。（）9.運(yùn)用簡(jiǎn)便方法計(jì)算分?jǐn)?shù)運(yùn)算一定會(huì)使計(jì)算更簡(jiǎn)單。（）10.分?jǐn)?shù)減法中，去括號(hào)時(shí)括號(hào)里的符號(hào)要變號(hào)。（）四、簡(jiǎn)答題（每題5分，共20分）1.簡(jiǎn)述分?jǐn)?shù)加法簡(jiǎn)便運(yùn)算的思路。答案：先觀察分?jǐn)?shù)特點(diǎn)，若有同分母分?jǐn)?shù)，可利用加法交換律、結(jié)合律先相加湊整；若分母不同，先通分再計(jì)算。2.計(jì)算\(\frac{3}{7}+\frac{2}{5}+\frac{4}{7}\)，并說明用到的運(yùn)算定律。答案：\(\frac{3}{7}+\frac{2}{5}+\frac{4}{7}=(\frac{3}{7}+\frac{4}{7})+\frac{2}{5}=1+\frac{2}{5}=\frac{7}{5}\)，用到加法交換律和結(jié)合律。3.如何運(yùn)用簡(jiǎn)便方法計(jì)算\(\frac{5}{8}-\frac{2}{7}-\frac{5}{7}\)？答案：根據(jù)減法性質(zhì)，\(\frac{5}{8}-\frac{2}{7}-\frac{5}{7}=\frac{5}{8}-(\frac{2}{7}+\frac{5}{7})=\frac{5}{8}-1=-\frac{3}{8}\)。4.說明分?jǐn)?shù)簡(jiǎn)便運(yùn)算與整數(shù)簡(jiǎn)便運(yùn)算的聯(lián)系。答案：二者聯(lián)系緊密，都運(yùn)用交換律、結(jié)合律等運(yùn)算定律。整數(shù)簡(jiǎn)便運(yùn)算思路可遷移到分?jǐn)?shù)運(yùn)算中，都是為使計(jì)算更簡(jiǎn)便。五、討論題（每題5分，共20分）1.討論在分?jǐn)?shù)混合運(yùn)算中，什么時(shí)候優(yōu)先使用簡(jiǎn)便運(yùn)算？答案：當(dāng)式子中有同分母分?jǐn)?shù)可湊整，或能通過交換律、結(jié)合律湊整時(shí)，優(yōu)先用簡(jiǎn)便運(yùn)算，可大大簡(jiǎn)化計(jì)算過程。2.分享你在做分?jǐn)?shù)簡(jiǎn)便運(yùn)算時(shí)容易出錯(cuò)的地方及如何避免？答案：易出錯(cuò)在通分不準(zhǔn)確、運(yùn)算定律使用不當(dāng)。避免方法是通分仔細(xì)找最小公倍數(shù)，牢記運(yùn)算定律，做題后認(rèn)真檢查。3.舉例說明生活中哪些地方會(huì)用到分?jǐn)?shù)簡(jiǎn)便運(yùn)算？答案：如分蛋糕，將蛋糕看作單位“1”，幾個(gè)人分不同份額，計(jì)算剩余或總共分出去多少時(shí)會(huì)用到；裝修計(jì)算用料比例等也會(huì)用到。4.如何引導(dǎo)同學(xué)更好地掌握分?jǐn)?shù)簡(jiǎn)便運(yùn)算？答案：先幫同學(xué)理解運(yùn)算定律含義，通過大量不同類型例題練習(xí)，讓其掌握技巧，遇到錯(cuò)題一起分析，多鼓勵(lì)增強(qiáng)信心。答案一、單項(xiàng)選擇題1.B2.