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{"segment":[{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/1.png' \/><\/center> <br\/> B\u1ed9i chung nh\u1ecf nh\u1ea5t c\u1ee7a hai hay nhi\u1ec1u s\u1ed1 l\u00e0 s\u1ed1 nh\u1ecf nh\u1ea5t trong t\u1eadp b\u1ed9i chung c\u1ee7a c\u00e1c s\u1ed1 \u0111\u00f3. \u0110\u00daNG <\/b> hay SAI <\/b>?","select":["A. \u0110\u00daNG ","B. SAI "],"hint":"","explain":"B\u00e0i gi\u1ea3i:<\/span> <br\/> B\u1ed9i chung nh\u1ecf nh\u1ea5t c\u1ee7a hai hay nhi\u1ec1u s\u1ed1 l\u00e0 s\u1ed1 nh\u1ecf nh\u1ea5t kh\u00e1c 0 <\/b> trong t\u1eadp h\u1ee3p b\u1ed9i chung c\u1ee7a c\u00e1c s\u1ed1 \u0111\u00f3. <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh tr\u00ean l\u00e0 SAI <\/b> ","column":2}]}],"id_ques":751},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/1.png' \/><\/center> <br\/>B\u1ed9i chung nh\u1ecf nh\u1ea5t c\u1ee7a s\u1ed1 t\u1ef1 nhi\u00ean a b\u1ea5t k\u00ec v\u00e0 1 l\u00e0 1. \u0110\u00daNG <\/b> hay SAI <\/b>?","select":["A. \u0110\u00daNG ","B. SAI "],"hint":"","explain":"B\u00e0i gi\u1ea3i:<\/span> <br\/> B\u1ed9i chung nh\u1ecf nh\u1ea5t c\u1ee7a s\u1ed1 t\u1ef1 nhi\u00ean a b\u1ea5t k\u00ec v\u00e0 1 l\u00e0 a <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh tr\u00ean l\u00e0 SAI <\/b> ","column":2}]}],"id_ques":752},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/10.jpg' \/><\/center> <br\/> BCNN(30; 45) = ?","select":["A. 45 ","B. 50 ","C. 60","D. 90"],"hint":"","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(30; 45) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> PH\u01af\u01a0NG PH\u00c1P CHUNG T\u00ccM BCNN <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch m\u1ed7i s\u1ed1 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3. <br\/> T\u00edch \u0111\u00f3 l\u00e0 BCNN ph\u1ea3i t\u00ecm <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 30; 45 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> Ta c\u00f3 $30 = 2 . 3 . 5$ ; $45 = 3^2 . 5$ <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang l\u00e0 2; 3; 5 <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 v\u1eeba ch\u1ecdn m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> BCNN(30; 45) = $2 . 3^2 . 5 = 90$ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: D. 90<\/span>","column":2}]}],"id_ques":753},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/10.jpg' \/><\/center> <br\/> BCNN(84; 120) = ?","select":["A. 420 ","B. 840 ","C. 640","D. 1020"],"hint":"","explain":"H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(84; 120) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> PH\u01af\u01a0NG PH\u00c1P CHUNG T\u00ccM BCNN <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch m\u1ed7i s\u1ed1 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3. <br\/> T\u00edch \u0111\u00f3 l\u00e0 BCNN ph\u1ea3i t\u00ecm <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 84; 120 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> Ta c\u00f3 $84 = 2^2 . 3 . 7$ ; $120 = 2^3 . 3 . 5$ <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang l\u00e0 2; 3; 5 v\u00e0 7<br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 v\u1eeba ch\u1ecdn m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> BCNN(84; 120) = $2^3 . 3 . 5 . 7 = 840$ <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. 840<\/span>","column":2}]}],"id_ques":754},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/10.jpg' \/><\/center> <br\/> BCNN(4; 7; 15) = ?","select":["A. 60 ","B. 28 ","C. 420","D. 210"],"hint":"","explain":" B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta th\u1ea5y (4; 7) = 1; (7; 15) = 1; (4; 15) = 1 <br\/> $\\Rightarrow$ BCNN(4; 7; 15) = 4 . 7 . 15 = 420 <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C. 420<\/span> <br\/> L\u01b0u \u00fd: N\u1ebfu c\u00e1c s\u1ed1 \u0111\u00e3 cho \u0111\u00f4i m\u1ed9t nguy\u00ean t\u1ed1 c\u00f9ng nhau th\u00ec BCNN c\u1ee7a ch\u00fang ch\u00ednh l\u00e0 t\u00edch c\u1ee7a c\u00e1c s\u1ed1 \u0111\u00f3 <\/i> <\/span> ","column":2}]}],"id_ques":755},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/9.jpg' \/><\/center> <br\/> T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean a nh\u1ecf nh\u1ea5t bi\u1ebft a $\\vdots$ 50; a $\\vdots$ 35","select":["A. a = 125 ","B. a = 350","C. a = 70","D. a = 175"],"hint":"S\u1ed1 t\u1ef1 nhi\u00ean a c\u1ea7n t\u00ecm ch\u00ednh l\u00e0 BCNN(50; 35)","explain":" B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec a nh\u1ecf nh\u1ea5t v\u00e0 a $\\vdots$ 50; a $\\vdots$ 35 <br\/> $\\Rightarrow$ a = BCNN(50; 35) <br\/> Ta c\u00f3: $50 = 2 . 5^2$ ; $35 = 5 . 7$ <br\/> $\\Rightarrow$ a = BCNN(50; 35) = $2 . 5^2 . 7 = 350$<br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B. a = 350<\/span> ","column":2}]}],"id_ques":756},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/9.jpg' \/><\/center> <br\/> T\u00ecm s\u1ed1 t\u1ef1 nhi\u00ean a nh\u1ecf nh\u1ea5t bi\u1ebft a $\\vdots$ 60; a $\\vdots$ 48","select":["A. a = 120 ","B. a = 80","C. a = 240","D. a = 360"],"hint":"S\u1ed1 t\u1ef1 nhi\u00ean a c\u1ea7n t\u00ecm ch\u00ednh l\u00e0 BCNN(60; 48)","explain":" B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec a nh\u1ecf nh\u1ea5t v\u00e0 a $\\vdots$ 60; a $\\vdots$ 48 <br\/> $\\Rightarrow$ a = BCNN(60; 48) <br\/> Ta c\u00f3: $60 = 2^2 . 3 . 5$ ; $48 = 2^4 . 3$ <br\/> $\\Rightarrow$ a = BCNN(60; 48) = $2^4 . 3 . 5 = 240$<br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C. a = 240<\/span> ","column":2}]}],"id_ques":757},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/11.jpg' \/><\/center> <br\/> BCNN(8; 12; 15) = 60. \u0110\u00daNG <\/b> hay SAI <\/b>","select":["A. \u0110\u00daNG ","B. SAI"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(8; 12; 15) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 8; 12; 15 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3. <br\/> T\u00edch \u0111\u00f3 l\u00e0 BCNN ph\u1ea3i t\u00ecm <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $8 = 2^3$ ; $12 = 2^2 . 3$ ; $15 = 3 . 5$ <br\/> $\\Rightarrow$ BCNN(8; 12; 15) = $2^3 . 3 . 5 = 120$ <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh \" BCNN(8; 15; 12) = 60 \" l\u00e0 SAI <\/b>","column":2}]}],"id_ques":758},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/11.jpg' \/><\/center> <br\/> BCNN(9; 24; 35) = 2520. \u0110\u00daNG <\/b> hay SAI <\/b>","select":["A. \u0110\u00daNG ","B. SAI"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(8; 12; 15) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 9; 24; 35 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3. <br\/> T\u00edch \u0111\u00f3 l\u00e0 BCNN ph\u1ea3i t\u00ecm <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $9 = 3^2$ ; $24 = 2^3 . 3$ ; $35 = 5 . 7$ <br\/> $\\Rightarrow$ BCNN(9; 24; 35) = $2^3 . 3^2 . 5 . 7 = 2520$ <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh \" BCNN(9; 24; 35) = 2520 \" l\u00e0 \u0110\u00daNG <\/b>","column":2}]}],"id_ques":759},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/4.jpg' \/><\/center> <br\/> T\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 300 c\u1ee7a 24; 25 l\u00e0:","select":["A. {0} ","B. $\\varnothing$","C. {0; 300}","D. {0; 150}"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(24; 25) r\u1ed3i t\u00ecm t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 300 c\u1ee7a 24; 25 <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 24; 25 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3, t\u00edch \u0111\u00f3 l\u00e0 BCNN <br\/> B\u01b0\u1edbc 4: <\/b> T\u00ecm t\u1eadp h\u1ee3p BC(24; 25) v\u00e0 nh\u1ecf h\u01a1n 300 b\u1eb1ng c\u00e1ch l\u1ea5y BCNN nh\u00e2n l\u1ea7n l\u01b0\u1ee3t v\u1edbi 0; 1; 2... <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $24 = 2^3 . 3$ ; $25 = 5^2$ <br\/> $\\Rightarrow$ BCNN(24; 25) = $2^3 . 3 . 5^2 = 600$ <br\/> $\\Rightarrow$ BC(24; 25) = {0; 600; 1200; 1800;.....} <br\/> Trong t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung \u1edf tr\u00ean ch\u1ec9 c\u00f3 0 < 300 <br\/> V\u1eady t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 300 c\u1ee7a 24; 25 l\u00e0 {0} <br\/> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0: A<\/span>","column":2}]}],"id_ques":760},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/4.jpg' \/><\/center> <br\/> T\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 200 c\u1ee7a 9; 24 l\u00e0:","select":["A. {0; 48; 72; 144} ","B. {0; 72; 144}","C. {0; 24; 72}","D. C\u1ea3 3 \u0111\u00e1p \u00e1n \u0111\u1ec1u sai"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(9; 24) r\u1ed3i t\u00ecm t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 200 c\u1ee7a 9; 24 <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch 9; 24 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3: <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 \u0111\u00e3 ch\u1ecdn, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a n\u00f3, t\u00edch \u0111\u00f3 l\u00e0 BCNN <br\/> B\u01b0\u1edbc 4: <\/b> T\u00ecm t\u1eadp h\u1ee3p BC(9; 24) v\u00e0 nh\u1ecf h\u01a1n 200 b\u1eb1ng c\u00e1ch l\u1ea5y BCNN nh\u00e2n l\u1ea7n l\u01b0\u1ee3t v\u1edbi 0; 1; 2... <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: $9 = 3^2$ ; $24 = 2^3 . 3$ <br\/> $\\Rightarrow$ BCNN(9; 24) = $2^3 . 3^2 = 72$ <br\/> $\\Rightarrow$ BC(9; 24) = {0; 72; 144; 216; 288;...} <br\/> T\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung nh\u1ecf h\u01a1n 200 c\u1ee7a 9; 24 l\u00e0: {0; 72; 144} <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B<\/span>","column":2}]}],"id_ques":761},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/2.jpg' \/><\/center> <br\/> Cho $a = 2^2 . 3^3 . 5$ <br\/> $b = 2^4 . 3 . 7$ <br\/> V\u1eady BCNN(a, b) = ?","select":["A. $2^2 . 3$ ","B. $2^4 . 3^3 . 5 . 7$","C. $2^4 . 3^3$","D. $5 . 7$"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> V\u00ec a, b \u0111\u00e3 ph\u00e2n t\u00edch ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 n\u00ean: <br\/> BCNN(a, b) b\u1eb1ng t\u00edch c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung l\u00e0: 2 v\u00e0 3 <br\/> (s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 2 l\u00e0 $2^4$; s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 3 l\u00e0 $3^3$) <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 ri\u00eang l\u00e0 5 v\u00e0 7 <br\/> (s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 5 v\u00e0 7 l\u00e0 1)<\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $a = 2^2 . 3^3 . 5$ <br\/> $b = 2^4 . 3 . 7$ <br\/> $\\Rightarrow$ BCNN(a; b) = $2^4 . 3^3 . 5 . 7$<br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B<\/span>","column":2}]}],"id_ques":762},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/2.jpg' \/><\/center> <br\/> Cho $a = 2. 3^3 . 11$ <br\/> $b = 2^4 . 3 . 5$ <br\/> V\u1eady BCNN(a, b) = ?","select":["A. $2^4 . 3^3$ ","B. $2 . 3 . 5 . 11$","C. $2^4 . 3^3 . 5 . 11$","D. $2 . 3^3$"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> V\u00ec a, b \u0111\u00e3 ph\u00e2n t\u00edch ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 n\u00ean: <br\/> BCNN(a, b) b\u1eb1ng t\u00edch c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung l\u00e0 2 v\u00e0 3 <br\/> (S\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 2 l\u00e0 $2^4$, s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 3 l\u00e0 $3^3$) <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 ri\u00eang l\u00e0 5; 11 <br\/> (S\u1ed1 m\u0169 c\u1ee7a 5 v\u00e0 11 l\u00e0 1) <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $a = 2. 3^3 . 11$ <br\/> $b = 2^4 . 3 . 5$ <br\/> $\\Rightarrow$ BCNN(a; b) = $2^4 . 3^3 . 5 . 11$<br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: C<\/span>","column":2}]}],"id_ques":763},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/2.jpg' \/><\/center> <br\/> Cho $a = 2 . 3^2 . 7$ <br\/> $b = 2^3 . 5 . 7$ <br\/> $c = 2^3 . 3^2$ <br\/> V\u1eady BCNN(a, b, c) = ?","select":["A. $2^3 . 3^2$ ","B. $2 . 3 . 5 . 7$","C. $3^2 . 5 . 7$","D. $2^3 . 3^2 . 5 . 7$"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> V\u00ec a, b, c \u0111\u00e3 ph\u00e2n t\u00edch ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 n\u00ean: <br\/> BCNN(a, b, c) b\u1eb1ng t\u00edch c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung l\u00e0 2<br\/> (S\u1ed1 m\u0169 l\u1edbn nh\u1ea5t c\u1ee7a 2 l\u00e0 $2^3$) <br\/> Th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 ri\u00eang l\u00e0 3; 5; 7 <br\/> (S\u1ed1 m\u0169 c\u1ee7a 3 l\u00e0 $3^2$, s\u1ed1 m\u0169 c\u1ee7a 5 v\u00e0 7 l\u00e0 1) <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $a = 2 . 3^2 . 7$ <br\/> $b = 2^3 . 5 . 7$ <br\/> $c = 2^3 . 3^2$ <br\/> $\\Rightarrow$ BCNN(a; b; c) = $2^3 . 3^2 . 5 . 7$<br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: D<\/span>","column":2}]}],"id_ques":764},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/13.jpg' \/><\/center> <br\/> T\u00ecm x bi\u1ebft x $\\in BC(6; 4)$, $16 \\leq x \\leq 50$?","select":["A. x = 24 ","B. x = 48","C. x = 36","D. C\u1ea3 3 \u0111\u00e1p \u00e1n \u0111\u1ec1u \u0111\u00fang"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Ta c\u00f3 th\u1ec3 t\u00ecm BCNN(6; 4) r\u1ed3i t\u00ecm t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung c\u1ee7a 6 v\u00e0 4 b\u1eb1ng c\u00e1ch l\u1ea5y BCNN nh\u00e2n l\u1ea7n l\u01b0\u1ee3t v\u1edbi c\u00e1c s\u1ed1 0; 1; 2;... <br\/> K\u1ebft h\u1ee3p \u0111i\u1ec1u ki\u1ec7n $16 \\leq x \\leq 50$ \u0111\u1ec3 t\u00ecm x <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $6 = 2 . 3$ ; $4 = 2^2$ <br\/> $\\Rightarrow$ BCNN(6; 4) = $2^2 . 3 = 12$ <br\/> $\\Rightarrow$ BC(6; 4) = {0; 12; 24; 36; 48; 60;...} <br\/> V\u00ec x $\\in BC(6; 4)$ v\u00e0 $16 \\leq x \\leq 50$ n\u00ean x = 24 ho\u1eb7c x = 36 ho\u1eb7c x = 48 <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: D<\/span>","column":2}]}],"id_ques":765},{"time":9,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/13.jpg' \/><\/center> <br\/> T\u00ecm x bi\u1ebft x $\\in BC(12; 18)$, $30 \\leq x \\leq 50$?","select":["A. x = 36 ","B. x = 56","C. x = 48","D. x = 72"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> Ta c\u00f3 th\u1ec3 t\u00ecm BCNN(12; 18) r\u1ed3i t\u00ecm t\u1eadp h\u1ee3p c\u00e1c b\u1ed9i chung c\u1ee7a 12 v\u00e0 18 b\u1eb1ng c\u00e1ch l\u1ea5y BCNN nh\u00e2n l\u1ea7n l\u01b0\u1ee3t v\u1edbi c\u00e1c s\u1ed1 0; 1; 2;... <br\/> K\u1ebft h\u1ee3p \u0111i\u1ec1u ki\u1ec7n $30\\leq x \\leq 50$ \u0111\u1ec3 t\u00ecm x <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> V\u00ec $18 = 2 . 3^2$ ; $12 = 2^2 . 3$ <br\/> $\\Rightarrow$ BCNN(12; 18) = $2^2 . 3^2 = 36$ <br\/> $\\Rightarrow$ BC(12; 18) = {0; 36; 72; 108;...} <br\/> V\u00ec x $\\in BC(12; 18)$ v\u00e0 $30 \\leq x \\leq 50$ n\u00ean x = 36 <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A<\/span>","column":2}]}],"id_ques":766},{"time":9,"part":[{"title":"","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":" L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t <br\/><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/3.jpg' \/><\/center>","select":["A. $BCNN(12; 20) = 60$ ","B. $BCNN(18; 15) = 30$"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(12; 20) v\u00e0 BCNN(18; 15) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> C\u00c1C B\u01af\u1edaC T\u00ccM BCNN <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch m\u1ed7i s\u1ed1 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3 : <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 \u0111\u00f3, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> \u0110\u00f3 ch\u00ednh l\u00e0 BCNN c\u1ea7n t\u00ecm<\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: <br\/> $12 = 2^2 . 3$; $20 = 2^2 . 5$ $\\Rightarrow$ BCNN(12; 20) = $2^2 . 3 . 5 = 60$ <br\/> $\\Rightarrow$ Kh\u1eb3ng \u0111\u1ecbnh \" BCNN(12; 20) = 60 \" l\u00e0 \u0110\u00daNG <\/b> <br\/> $18 = 2 . 3^2$ ; $15 = 3 . 5$ $\\Rightarrow$ BCNN(18; 15) = $2 . 3^2 . 5 = 90$ <br\/> $\\Rightarrow$ Kh\u1eb3ng \u0111\u1ecbnh \" BCNN(18; 15) = 30 \" l\u00e0 SAI <\/b> <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: A<\/span>","column":2}]}],"id_ques":767},{"time":9,"part":[{"title":"","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":" L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t <br\/><center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/3.jpg' \/><\/center>","select":["A. $BCNN(9; 24) = 216$ ","B. $BCNN(24; 10) = 120$"],"hint":"","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> T\u00ecm BCNN(9; 24) v\u00e0 BCNN(24; 10) r\u1ed3i ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang <br\/> C\u00c1C B\u01af\u1edaC T\u00ccM BCNN <br\/> B\u01b0\u1edbc 1: <\/b> Ph\u00e2n t\u00edch m\u1ed7i s\u1ed1 ra th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 <br\/> B\u01b0\u1edbc 2: <\/b> Ch\u1ecdn ra c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 chung v\u00e0 ri\u00eang <br\/> B\u01b0\u1edbc 3 : <\/b> L\u1eadp t\u00edch c\u00e1c th\u1eeba s\u1ed1 nguy\u00ean t\u1ed1 \u0111\u00f3, m\u1ed7i th\u1eeba s\u1ed1 l\u1ea5y v\u1edbi s\u1ed1 m\u0169 l\u1edbn nh\u1ea5t <br\/> \u0110\u00f3 ch\u00ednh l\u00e0 BCNN c\u1ea7n t\u00ecm<\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> Ta c\u00f3: <br\/> $9 = 3^2$; $24 = 2^3 . 3$ $\\Rightarrow$ BCNN(9; 24) = $2^3 . 3^2 = 72$ <br\/> $\\Rightarrow$ Kh\u1eb3ng \u0111\u1ecbnh \" BCNN(9; 24) = 216 \" l\u00e0 SAI <\/b> <br\/> $24 = 2^3 . 3$ ; $10 = 2 . 5$ $\\Rightarrow$ BCNN(24; 10) = $2^3 . 3 . 5 = 120$ <br\/> $\\Rightarrow$ Kh\u1eb3ng \u0111\u1ecbnh \" BCNN(24; 10) = 120 \" l\u00e0 \u0110\u00daNG <\/b> <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B<\/span>","column":2}]}],"id_ques":768},{"time":9,"part":[{"title":" L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/8.jpg' \/><\/center> <br\/> S\u1ed1 h\u1ecdc sinh l\u1edbp 6A khi x\u1ebfp h\u00e0ng 3, h\u00e0ng 4, h\u00e0ng 5 \u0111\u1ec1u v\u1eeba \u0111\u1ee7 h\u00e0ng. Bi\u1ebft s\u1ed1 h\u1ecdc sinh l\u1edbp \u0111\u00f3 kho\u1ea3ng t\u1eeb 45 \u0111\u1ebfn 65 h\u1ecdc sinh. T\u00ednh s\u1ed1 h\u1ecdc sinh l\u1edbp 6A?","select":["A. 50 h\u1ecdc sinh","B. 60 h\u1ecdc sinh","C. 45 h\u1ecdc sinh","D. 54 h\u1ecdc sinh"],"hint":"S\u1ed1 h\u1ecdc sinh thu\u1ed9c t\u1eadp BC(3; 4; 5)","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> N\u1ebfu s\u1ed1 h\u1ecdc sinh l\u1edbp 6A l\u00e0 x (h\u1ecdc sinh) <br\/> Khi \u0111\u00f3 x $\\vdots$ 3; x $\\vdots$ 4 v\u00e0 x $\\vdots$ 5 n\u00ean x $\\in$ BC(3; 4; 5) <br\/> Ta \u0111i t\u00ecm x th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n 45 < x < 65 <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> G\u1ecdi s\u1ed1 h\u1ecdc sinh l\u1edbp 6A l\u00e0 x (45 < x < 65) <br\/> V\u00ec khi x\u1ebfp h\u00e0ng 3, h\u00e0ng 4 hay h\u00e0ng 5 \u0111\u1ec1u v\u1eeba \u0111\u1ee7 h\u00e0ng n\u00ean x $\\vdots$ 3; x $\\vdots$ 4; x $\\vdots$ 5 <br\/> $\\Rightarrow$ x $\\in$ BC(3; 4; 5) = {0; 60; 120; 180; 240;...} <br\/> V\u00ec 45 < x < 65 n\u00ean x = 60 <br\/> V\u1eady l\u1edbp 6A c\u00f3 60 h\u1ecdc sinh <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B<\/span>","column":2}]}],"id_ques":769},{"time":9,"part":[{"title":" L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t ","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop6/toan/daiso/bai16/lv1/img\/8.jpg' \/><\/center> <br\/> S\u1ed1 h\u1ecdc sinh l\u1edbp 6B khi x\u1ebfp h\u00e0ng 8, h\u00e0ng 5 hay h\u00e0ng 10 \u0111\u1ec1u v\u1eeba \u0111\u1ee7. Bi\u1ebft s\u1ed1 h\u1ecdc sinh l\u1edbp \u0111\u00f3 kho\u1ea3ng t\u1eeb 35 \u0111\u1ebfn 60 h\u1ecdc sinh. T\u00ednh s\u1ed1 h\u1ecdc sinh l\u1edbp 6B?","select":["A. 60 h\u1ecdc sinh","B. 40 h\u1ecdc sinh","C. 45 h\u1ecdc sinh","D. 50 h\u1ecdc sinh"],"hint":"S\u1ed1 h\u1ecdc sinh thu\u1ed9c t\u1eadp BC(8; 5; 10)","explain":" H\u01b0\u1edbng d\u1eabn:<\/span><br\/> N\u1ebfu s\u1ed1 h\u1ecdc sinh l\u1edbp 6B l\u00e0 x (h\u1ecdc sinh) <br\/> Khi \u0111\u00f3 x $\\vdots$ 8; x $\\vdots$ 5 v\u00e0 x $\\vdots$ 10 n\u00ean x $\\in$ BC(8; 5; 10) <br\/> Ta \u0111i t\u00ecm x th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n 35 < x < 60 <\/span> <br\/><br\/> B\u00e0i gi\u1ea3i:<\/span> <br\/> G\u1ecdi s\u1ed1 h\u1ecdc sinh l\u1edbp 6B l\u00e0 x (35 < x < 60) <br\/> V\u00ec khi x\u1ebfp h\u00e0ng 8, h\u00e0ng 5 hay h\u00e0ng 10 \u0111\u1ec1u v\u1eeba \u0111\u1ee7 n\u00ean x $\\vdots$ 8; x $\\vdots$ 5; x $\\vdots$ 10 <br\/> $\\Rightarrow$ x $\\in$ BC(8; 5; 10) = {0; 40; 80; 120; 160;...} <br\/> V\u00ec 35 < x < 60 n\u00ean x = 40 <br\/> V\u1eady l\u1edbp 6B c\u00f3 40 h\u1ecdc sinh <br\/> V\u1eady \u0111\u00e1p \u00e1n \u0111\u00fang l\u00e0: B<\/span>","column":2}]}],"id_ques":770}],"lesson":{"save":0,"level":1}}

Điểm của bạn.

Câu hỏi này theo dạng chọn đáp án đúng, sau khi đọc xong câu hỏi, bạn bấm vào một trong số các đáp án mà chương trình đưa ra bên dưới, sau đó bấm vào nút gửi để kiểm tra đáp án và sẵn sàng chuyển sang câu hỏi kế tiếp

Trả lời đúng trong khoảng thời gian quy định bạn sẽ được + số điểm như sau:
Trong khoảng 1 phút đầu tiên	+ 5 điểm
Trong khoảng 1 phút -> 2 phút	+ 4 điểm
Trong khoảng 2 phút -> 3 phút	+ 3 điểm
Trong khoảng 3 phút -> 4 phút	+ 2 điểm
Trong khoảng 4 phút -> 5 phút	+ 1 điểm

Quá 5 phút: không được cộng điểm

Tổng thời gian làm mỗi câu (không giới hạn)

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Bấm vào đây nếu phát hiện có lỗi hoặc muốn gửi góp ý

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