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Home Lớp 6 Toán lớp 6 - Sách kết nối tri thức Phép trừ phân sốBài tập trung bình

{"common":{"save":0,"post_id":"805","level":2,"total":20,"point":5,"point_extra":0},"segment":[{"id":"1621","post_id":"805","mon_id":"0","chapter_id":"0","question":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","options":{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c: $1 - \\dfrac{-1}{4} + \\dfrac{-5}{9} - \\dfrac{7}{12}$ l\u00e0: ","select":["A. $\\dfrac{8}{9}$ ","B. $\\dfrac{-1}{9}$ ","C. $\\dfrac{1}{9}$","D. $\\dfrac{-7}{18}$ "],"hint":"Quy \u0111\u1ed3ng r\u1ed3i th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: <\/b>Quy \u0111\u1ed3ng c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean v\u1edbi m\u1eabu s\u1ed1 chung l\u00e0 36 <br\/> B\u01b0\u1edbc 2: <\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh theo quy t\u1eafc c\u1ed9ng, tr\u1eeb c\u00e1c ph\u00e2n s\u1ed1 c\u00f9ng m\u1eabu <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} & 1 - \\dfrac{-1}{4} + \\dfrac{-5}{9} - \\dfrac{7}{12} \\\\ &= \\dfrac{1 . 36}{1 . 36} - \\dfrac{-1 . 9}{4 . 9} + \\dfrac{-5 . 4}{9 . 4} - \\dfrac{7 . 3}{12 . 3} \\\\ &= \\dfrac{36}{36} - \\dfrac{-9}{36} + \\dfrac{-20}{36} - \\dfrac{21}{36} \\\\ &= \\dfrac{36 - (-9) + (-20) - 21}{36} \\\\ &= \\dfrac{36 + 9 - 20 - 21}{36} \\\\ &= \\dfrac{4}{36} \\\\ &= \\dfrac{1}{9} \\end{align*}$ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C <\/span> <br\/> L\u01b0u \u00fd: H\u1ecdc sinh hay m\u1eafc sai l\u1ea7m khi b\u1ecf ngo\u1eb7c m\u00e0 \u0111\u1eb1ng tr\u01b0\u1edbc d\u1ea5u ngo\u1eb7c c\u00f3 d\u1ea5u tr\u1eeb ta kh\u00f4ng \u0111\u1ed5i d\u1ea5u c\u1ee7a ph\u00e9p t\u00ednh trong ngo\u1eb7c d\u1eabn \u0111\u1ebfn t\u00ednh to\u00e1n sai <\/i><\/span> ","column":4}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:53"},{"id":"1622","post_id":"805","mon_id":"0","chapter_id":"0","question":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","options":{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c: $ \\dfrac{25}{48} + \\dfrac{7}{12} - \\dfrac{9}{16} - \\dfrac{1}{8} $ l\u00e0: ","select":["A. $\\dfrac{-2}{3}$ ","B. $\\dfrac{2}{3}$ ","C. $\\dfrac{-5}{12}$","D. $\\dfrac{5}{12}$ "],"hint":"Quy \u0111\u1ed3ng v\u00e0 th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: <\/b>Quy \u0111\u1ed3ng c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean v\u1edbi m\u1eabu s\u1ed1 chung l\u00e0 48 <br\/> B\u01b0\u1edbc 2: <\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh theo quy t\u1eafc c\u1ed9ng, tr\u1eeb c\u00e1c ph\u00e2n s\u1ed1 c\u00f9ng m\u1eabu <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} & \\dfrac{25}{48} + \\dfrac{7}{12} - \\dfrac{9}{16} - \\dfrac{1}{8} \\\\ &= \\dfrac{25}{48} + \\dfrac{7 . 4}{12 . 4} - \\dfrac{9 . 3}{16 . 3} - \\dfrac{1 . 6}{8 . 6} \\\\ &= \\dfrac{25}{48} + \\dfrac{28}{48} - \\dfrac{27}{48} - \\dfrac{6}{48} \\\\ &= \\dfrac{25 + 28 - 27 - 6}{48} \\\\ &= \\dfrac{20}{48} \\\\ &= \\dfrac{20 : 4}{48 : 4} \\\\ &= \\dfrac{5}{12} \\end{align*}$ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: D <\/span> <br\/> Nh\u1eadn x\u00e9t: N\u00ean r\u00fat g\u1ecdn v\u1ec1 ph\u00e2n s\u1ed1 t\u1ed1i gi\u1ea3n tr\u01b0\u1edbc v\u00e0 sau khi th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh <\/i><\/span> ","column":4}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:53"},{"id":"1623","post_id":"805","mon_id":"0","chapter_id":"0","question":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","options":{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Gi\u00e1 tr\u1ecb c\u1ee7a bi\u1ec3u th\u1ee9c: $ \\dfrac{11}{-16} - \\dfrac{7}{20} + \\dfrac{43}{80}$ l\u00e0: ","select":["A. $\\dfrac{-1}{2}$ ","B. $\\dfrac{1}{2}$ ","C. $\\dfrac{7}{8}$","D. $\\dfrac{-7}{8}$ "],"hint":"","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> <b< B\u01b0\u1edbc 1: <\/b> \u0110\u01b0a ph\u00e2n s\u1ed1 $\\dfrac{11}{-16}$ v\u1ec1 m\u1eabu d\u01b0\u01a1ng <br\/> B\u01b0\u1edbc 2: <\/b>Quy \u0111\u1ed3ng c\u00e1c ph\u00e2n s\u1ed1 tr\u00ean v\u1edbi m\u1eabu s\u1ed1 chung l\u00e0 80 <br\/> B\u01b0\u1edbc 3: <\/b> Th\u1ef1c hi\u1ec7n ph\u00e9p t\u00ednh theo quy t\u1eafc c\u1ed9ng, tr\u1eeb c\u00e1c ph\u00e2n s\u1ed1 c\u00f9ng m\u1eabu <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> $\\begin{align*} & \\dfrac{11}{-16} - \\dfrac{7}{20} + \\dfrac{43}{80} \\\\ &= \\dfrac{11 . (-1)}{-16 . (-1)} - \\dfrac{7}{20} - \\dfrac{43}{80} \\\\ &= \\dfrac{-11 . 5}{16 . 5} - \\dfrac{7 . 4}{20 . 4} + \\dfrac{43}{80} \\\\ &= \\dfrac{-55}{50} - \\dfrac{28}{80} + \\dfrac{43}{80} \\\\ &= \\dfrac{-55 - 28 + 43}{80} \\\\ &= \\dfrac{-40}{80} \\\\ &= \\dfrac{-40 : 40}{80 : 40} \\\\ &= \\dfrac{-1}{2} \\end{align*}$ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A <\/span> ","column":4}]}]},"correct":"","level":"2","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:53"}]}