Quy đồng mẫu nhiều phân số. So sánh phân số-level1

Home Lớp 6 Toán lớp 6 - Sách kết nối tri thức Quy đồng mẫu nhiều phân số. So sánh phân sốBài tập cơ bản

{"common":{"save":0,"post_id":"798","level":1,"total":20,"point":5,"point_extra":0},"segment":[{"id":"1501","post_id":"798","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":"Quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1: $\\dfrac{7}{30}; \\dfrac{8}{45}; \\dfrac{-11}{90}$ ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1:","select":["A. $\\dfrac{7}{90}; \\dfrac{16}{90}; \\dfrac{-11}{90} $ ","B. $\\dfrac{211}{90}; \\dfrac{-16}{90}; \\dfrac{-11}{90} $ ","C. $\\dfrac{21}{90}; \\dfrac{16}{90}; \\dfrac{-11}{90} $","D. $\\dfrac{-7}{90}; \\dfrac{-16}{90}; \\dfrac{-11}{90} $ "],"hint":"\u00c1p d\u1ee5ng quy t\u1eafc quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: <\/b> T\u00ecm m\u1eabu s\u1ed1 chung (MSC) <br\/> MSC = BCNN(30, 45, 90) = ? <br\/> B\u01b0\u1edbc 2: <\/b> T\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 (TSP) c\u1ee7a c\u00e1c ph\u00e2n s\u1ed1: <br\/> Th\u1eeba s\u1ed1 ph\u1ee5 c\u1ee7a ph\u00e2n s\u1ed1: $\\dfrac{7}{30}$ l\u00e0: MSC : 30 = ? <br\/> T\u01b0\u01a1ng t\u1ef1 ta t\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i <br\/> B\u01b0\u1edbc 3: <\/b> Quy \u0111\u1ed3ng <br\/> $\\dfrac{7}{30} = \\dfrac{7 . TSP}{30 . TSP}$ c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i ta l\u00e0m t\u01b0\u01a1ng t\u1ef1 <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> Ph\u00e2n t\u00edch c\u00e1c s\u1ed1 30, 45, 90 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 ta \u0111\u01b0\u1ee3c: <br\/> $30 = 2 . 3 . 5$ <br\/> $45 = 3^2 . 5$ <br\/> $90 = 2 . 3^2 . 5$ <br\/> M\u1eabu s\u1ed1 chung = BCNN(30, 45, 90) = $2 . 3^2 . 5 = 90$ <br\/> Th\u1eeba s\u1ed1 ph\u1ee5: 90 : 30 = 3; 90 : 45 = 2 <br\/> Quy \u0111\u1ed3ng: <br\/> $\\dfrac{7}{30} = \\dfrac{7 . 3}{30 . 3} = \\dfrac{21}{90}$ <br\/> $\\dfrac{8}{45} = \\dfrac{8 . 2}{45 . 2} = \\dfrac{16}{90}$ <br\/> V\u1eady c\u00e1c ph\u00e2n s\u1ed1 $\\dfrac{7}{30}; \\dfrac{8}{45}; \\dfrac{-11}{90}$ sau khi quy \u0111\u1ed3ng ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1 l\u00e0: $\\dfrac{21}{90}; \\dfrac{16}{90}; \\dfrac{-11}{90} $ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C <\/span> ","column":2}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:52"},{"id":"1502","post_id":"798","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":[[2]],"list":[{"point":5,"ques":"Quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1: $\\dfrac{-4}{5}; \\dfrac{1}{6}; \\dfrac{-9}{7}$ ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1:","select":["A. $\\dfrac{168}{210}; \\dfrac{35}{210}; \\dfrac{270}{210} $ ","B. $\\dfrac{-168}{210}; \\dfrac{35}{210}; \\dfrac{-270}{210} $ ","C. $\\dfrac{-4}{210}; \\dfrac{35}{210}; \\dfrac{-9}{210} $","D. $\\dfrac{-41}{210}; \\dfrac{35}{210}; \\dfrac{-30}{210} $ "],"hint":"\u00c1p d\u1ee5ng quy t\u1eafc quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: <\/b> T\u00ecm m\u1eabu s\u1ed1 chung (MSC) <br\/> MSC = BCNN(5, 6, 7) = ? <br\/> B\u01b0\u1edbc 2: <\/b> T\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 (TSP) c\u1ee7a c\u00e1c ph\u00e2n s\u1ed1: <br\/> Th\u1eeba s\u1ed1 ph\u1ee5 c\u1ee7a ph\u00e2n s\u1ed1: $\\dfrac{-4}{5}$ l\u00e0: MSC : 5 = ? <br\/> T\u01b0\u01a1ng t\u1ef1 ta t\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i <br\/> B\u01b0\u1edbc 3: <\/b> Quy \u0111\u1ed3ng <br\/> $\\dfrac{-4}{5} = \\dfrac{-4 . TSP}{5 . TSP}$ c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i ta l\u00e0m t\u01b0\u01a1ng t\u1ef1 <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> M\u1eabu s\u1ed1 chung = BCNN(5, 6, 7) = $2 . 3 . 5 . 7 = 210$ <br\/> Th\u1eeba s\u1ed1 ph\u1ee5: 210 : 5 = 42; 210 : 6 = 35; 210 : 7 = 30 <br\/> Quy \u0111\u1ed3ng: <br\/> $\\dfrac{-4}{5} = \\dfrac{-4 . 42}{5 . 42} = \\dfrac{-168}{210}$ <br\/> $\\dfrac{1}{6} = \\dfrac{1 . 35}{6 . 35} = \\dfrac{35}{210}$ <br\/> $\\dfrac{-9}{7} = \\dfrac{-9 . 30}{7 . 30} = \\dfrac{-270}{210}$ <br\/> V\u1eady c\u00e1c ph\u00e2n s\u1ed1 $\\dfrac{-4}{5}; \\dfrac{1}{6}; \\dfrac{-9}{7}$ sau khi quy \u0111\u1ed3ng ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1 l\u00e0: $\\dfrac{-168}{210}; \\dfrac{35}{210}; \\dfrac{-270}{210} $ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B <\/span> ","column":2}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:52"},{"id":"1503","post_id":"798","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":"Quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1: $\\dfrac{5}{14}; \\dfrac{13}{21}; \\dfrac{20}{49}$ ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1:","select":["A. $\\dfrac{105}{294}; \\dfrac{182}{294}; \\dfrac{120}{294} $ ","B. $\\dfrac{-105}{294}; \\dfrac{-182}{294}; \\dfrac{120}{294} $ ","C. $\\dfrac{21}{294}; \\dfrac{182}{294}; \\dfrac{120}{294} $","D. $\\dfrac{211}{294}; \\dfrac{14}{294}; \\dfrac{120}{294} $ "],"hint":"\u00c1p d\u1ee5ng quy t\u1eafc quy \u0111\u1ed3ng m\u1eabu c\u00e1c ph\u00e2n s\u1ed1","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> B\u01b0\u1edbc 1: <\/b> T\u00ecm m\u1eabu s\u1ed1 chung (MSC) <br\/> MSC = BCNN(14, 21, 49) = ? <br\/> B\u01b0\u1edbc 2: <\/b> T\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 (TSP) c\u1ee7a c\u00e1c ph\u00e2n s\u1ed1: <br\/> Th\u1eeba s\u1ed1 ph\u1ee5 c\u1ee7a ph\u00e2n s\u1ed1: $\\dfrac{5}{14}$ l\u00e0: MSC : 14 = ? <br\/> T\u01b0\u01a1ng t\u1ef1 ta t\u00ecm th\u1eeba s\u1ed1 ph\u1ee5 c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i <br\/> B\u01b0\u1edbc 3: <\/b> Quy \u0111\u1ed3ng <br\/> $\\dfrac{5}{14} = \\dfrac{5 . TSP}{14 . TSP}$ c\u00e1c ph\u00e2n s\u1ed1 c\u00f2n l\u1ea1i ta l\u00e0m t\u01b0\u01a1ng t\u1ef1 <\/span> <br\/><br\/>B\u00e0i gi\u1ea3i:<\/span> <br\/> Ph\u00e2n t\u00edch c\u00e1c s\u1ed1 14, 21, 49 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 ta \u0111\u01b0\u1ee3c: <br\/> $14 = 2 . 7$ <br\/> $21 = 3 . 7$ <br\/> $49 = 7^2$ <br\/> M\u1eabu s\u1ed1 chung = BCNN(14, 21, 49) = $2 . 3 . 7^2 = 294$ <br\/> Th\u1eeba s\u1ed1 ph\u1ee5: 294 : 14 = 21; 294 : 21 = 14; 294 : 49 = 6 <br\/> Quy \u0111\u1ed3ng: <br\/> $\\dfrac{5}{14} = \\dfrac{5 . 21}{14 . 21} = \\dfrac{105}{294}$ <br\/> $\\dfrac{13}{21} = \\dfrac{13 . 14}{21 . 14} = \\dfrac{182}{294}$ <br\/> $\\dfrac{20}{49} = \\dfrac{20 . 6}{49 . 6} = \\dfrac{120}{294}$ <br\/> V\u1eady c\u00e1c ph\u00e2n s\u1ed1 $\\dfrac{5}{14}; \\dfrac{13}{21}; \\dfrac{20}{49}$ sau khi quy \u0111\u1ed3ng ta \u0111\u01b0\u1ee3c c\u00e1c ph\u00e2n s\u1ed1 l\u00e0: $\\dfrac{105}{294}; \\dfrac{182}{294}; \\dfrac{120}{294} $ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A <\/span> ","column":2}]}]},"correct":"","level":"1","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:14:52"}]}