{"id":2643,"date":"2021-10-14T21:16:16","date_gmt":"2021-10-14T14:16:16","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=2643"},"modified":"2021-10-14T22:11:11","modified_gmt":"2021-10-14T15:11:11","slug":"nhu%cc%83ng-dieu-can-biet-ve-ti%cc%89-le%cc%a3-thuc-gioi-toan-lop-7","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/nhu%cc%83ng-dieu-can-biet-ve-ti%cc%89-le%cc%a3-thuc-gioi-toan-lop-7\/","title":{"rendered":"Nh\u01b0\u0303ng \u0111i\u00ea\u0300u c\u00e2\u0300n bi\u00ea\u0301t v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c \u2013 Gi\u1ecfi to\u00e1n l\u1edbp 7"},"content":{"rendered":"\n<p>Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn<\/p>\n\n\n\n<p>\u01a0\u0309 ba\u0300i tr\u01b0\u01a1\u0301c, Vietlearn \u0111a\u0303 cu\u0300ng ca\u0301c ba\u0323n ho\u0323c sinh ti\u0300m hi\u00ea\u0309u ca\u0301c ki\u00ea\u0301n th\u01b0\u0301c v\u00ea\u0300 lu\u0303y th\u01b0\u0300a. V\u01a1\u0301i ba\u0300i vi\u00ea\u0301t na\u0300y, chu\u0301ng ta se\u0303 ti\u0300m hi\u00ea\u0309u ph\u00e2\u0300n ki\u00ea\u0301n th\u01b0\u0301c m\u01a1\u0301i. Trong ch\u01b0\u01a1ng tri\u0300nh Toa\u0301n 7, ca\u0301c ba\u0323n ho\u0323c sinh se\u0303 ti\u0300m hi\u00ea\u0309u v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c. \u0110\u00e2y la\u0300 m\u00f4\u0323t trong nh\u01b0\u0303ng ph\u00e2\u0300n ki\u00ea\u0301n th\u01b0\u0301c quan tro\u0323ng c\u00e2\u0300n n\u0103\u0301m v\u01b0\u0303ng. Ti\u0309 l\u00ea\u0323 th\u01b0\u0301c la\u0300 gi\u0300? Ca\u0301c da\u0323ng ba\u0300i t\u00e2\u0323p v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c se\u0303 \u0111\u01b0\u01a1\u0323c Vietlearn t\u00f4\u0309ng h\u01a1\u0323p trong ba\u0300i vi\u00ea\u0301t sau:<\/p>\n\n\n\n<p>Ki\u00ea\u0301n th\u01b0\u0301c c\u00e2\u0300n nh\u01a1\u0301 v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c<\/p>\n\n\n\n<p>\u0110i\u0323nh nghi\u0303a<\/p>\n\n\n\n<p>\u0110\u0103\u0309ng th\u01b0\u0301c a\/b = c\/d \u0111\u01b0\u01a1\u0323c go\u0323i la\u0300 m\u00f4\u0323t ti\u0309 l\u00ea\u0323 th\u01b0\u0301c trong \u0111o\u0301:<\/p>\n\n\n\n<p>Ngoa\u0323i ti\u0309 la\u0300 a va\u0300 d.<\/p>\n\n\n\n<p>Trung ti\u0309 la\u0300 b va\u0300 c.<\/p>\n\n\n\n<p>Vi\u0301 du\u0323 minh ho\u0323a: Trong \u0111\u0103\u0309ng th\u01b0\u0301c 4\/8 = 1\/2 ta co\u0301:<\/p>\n\n\n\n<p>Ngoa\u0323i ti\u0309 la\u0300 4 va\u0300 2.<\/p>\n\n\n\n<p>Trung ti\u0309 la\u0300 8 va\u0300 1.<\/p>\n\n\n\n<p>Ti\u0301nh ch\u00e2\u0301t<\/p>\n\n\n\n<p>Ti\u0301nh ch\u00e2\u0301t 1: Cho \u0111\u0103\u0309ng th\u01b0\u0301c a\/b = c\/d =&gt; a x d = b x c<\/p>\n\n\n\n<p>Vi\u0301 du\u0323 minh ho\u0323a: \u0110\u0103\u0309ng th\u01b0\u0301c 4\/8 = 1\/2 =&gt; 4 x 2 = 8 x 1<\/p>\n\n\n\n<p>Ti\u0301nh ch\u00e2\u0301t 2: \u0110i\u00ea\u0300u ki\u00ea\u0323n \u0111\u00ea\u0309 tha\u0300nh l\u00e2\u0323p m\u00f4\u0323t \u0111\u0103\u0309ng th\u01b0\u0301c:<\/p>\n\n\n\n<p>Ti\u0301nh ch\u00e2\u0301t ti\u0309 l\u00ea\u0323 th\u01b0\u0301c<\/p>\n\n\n\n<p>Ta co\u0301: a x d = b x c va\u0300 a, b, c, d kha\u0301c 0 ta c\u00e2\u0300n co\u0301 ca\u0301c ti\u0309 l\u00ea\u0323 th\u01b0\u0301c:<\/p>\n\n\n\n<p>a\/b = c\/d ; a\/c = b\/d ; d\/b = c\/a ; d\/c = b\/a<\/p>\n\n\n\n<p>Vi\u0301 du\u0323 minh ho\u0323a: 2 x 3 = 6 x 1<\/p>\n\n\n\n<p>2\/6 = 1\/3 ; 2\/1 = 6\/3 ; 3\/6 = 1\/2 ; 3\/1 = 6\/2<\/p>\n\n\n\n<p>\u0110o\u0323c th\u00eam: Ho\u0323c Toa\u0301n 7 cu\u0300ng Vietlearn: T\u00f4\u0309ng h\u01a1\u0323p ki\u00ea\u0301n th\u01b0\u0301c v\u00ea\u0300 lu\u0303y th\u01b0\u0300a cu\u0309a m\u00f4\u0323t s\u00f4\u0301 h\u01b0\u0303u ti\u0309<\/p>\n\n\n\n<p>Da\u0323ng toa\u0301n c\u01a1 ba\u0309n v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c<\/p>\n\n\n\n<p>Da\u0323ng 1: T\u01b0\u0300 \u0111\u0103\u0309ng th\u01b0\u0301c co\u0301 s\u0103\u0303n l\u00e2\u0323p ti\u0309 l\u00ea\u0323 th\u01b0\u0301c<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng pha\u0301p: Ta s\u01b0\u0309 du\u0323ng ti\u0301nh ch\u00e2\u0301t 2 cu\u0309a ti\u0309 l\u00ea\u0323 th\u01b0\u0301c.<\/p>\n\n\n\n<p>Ta co\u0301: a x d = b x c va\u0300 a, b, c, d kha\u0301c 0 ta c\u00e2\u0300n co\u0301 ca\u0301c ti\u0309 l\u00ea\u0323 th\u01b0\u0301c:<\/p>\n\n\n\n<p>a\/b = c\/d ; a\/c = b\/d ; d\/b = c\/a ; d\/c = b\/a<\/p>\n\n\n\n<p>Vi\u0301 du\u0323 minh ho\u0323a: 4 x 3 = 6 x 2<\/p>\n\n\n\n<p>4\/6 = 2\/3 ; 4\/2 = 6\/3 ; 3\/6 = 2\/4 ; 3\/2 = 6\/4<\/p>\n\n\n\n<p>Da\u0323ng 2: Ti\u0300m x, y tho\u0309a ma\u0303n \u0111i\u00ea\u0300u ki\u00ea\u0323n<\/p>\n\n\n\n<p>Ph\u01b0\u01a1ng pha\u0301p: Ta s\u01b0\u0309 dung ti\u0301ch ch\u00e2\u0301t 1 cu\u0309a ti\u0309 l\u00ea\u0323 th\u01b0\u0301c.<\/p>\n\n\n\n<p>a\/b = c\/d =&gt; a x d = b x c<\/p>\n\n\n\n<p>Vi\u0301 du\u0323: x\/2 = 6\/4<\/p>\n\n\n\n<p>=&gt; x . 4 = 2 . 6<\/p>\n\n\n\n<p>=&gt; x . 4 = 12<\/p>\n\n\n\n<p>=&gt; x = 3<\/p>\n\n\n\n<p>Ba\u0300i t\u00e2\u0323p v\u00e2\u0323n du\u0323ng<\/p>\n\n\n\n<p>Ba\u0300i 1: Ti\u0300m x tho\u0309a ma\u0303 ca\u0301c ti\u0309 l\u00ea\u0323 th\u01b0\u0301c:<\/p>\n\n\n\n<p>a. (x -1) : ( x- 2) = (x + 4) : (x +7)<\/p>\n\n\n\n<p>b. (x -1) : (x + 5) = 6\/7<\/p>\n\n\n\n<p>c. x^2 : 6 = 24\/25<\/p>\n\n\n\n<p>d. ( 4 \u2013 3\/4 ) : ( 7\/3 \u2013 10\/9) = 31x : ( 30\/7 \u2013 2\/13)<\/p>\n\n\n\n<p>e. x\/7 = y\/13 va\u0300 x + y = 25<\/p>\n\n\n\n<p>g. x^2 : 9 = y^2 : 16 va\u0300 x^2 + y^2 = 100<\/p>\n\n\n\n<p>Ba\u0300i 2: Ti\u0300m ca\u0301c s\u00f4\u0301 x, y, z:<\/p>\n\n\n\n<p>x\/3 = y\/2, y\/5 = z\/3, x + y + z = 46<\/p>\n\n\n\n<p>Toa\u0301n v\u00e2\u0323n du\u0323ng cao<\/p>\n\n\n\n<p>Ba\u0300i 1: C\u00f4ng ty A co\u0301 130 ng\u01b0\u01a1\u0300i \u0111i tr\u00f4\u0300ng c\u00e2y, chia tha\u0300nh 3 nho\u0301m: 1, 2, 3. M\u00f4\u0303i ng\u01b0\u01a1\u0300i \u0111\u00f4\u0323i 1 tr\u00f4\u0300ng \u0111\u01b0\u01a1\u0323c 2 c\u00e2y. M\u00f4\u0303i ng\u01b0\u01a1\u0300i trong \u0111\u00f4\u0323i 2 tr\u00f4\u0300ng \u0111\u01b0\u01a1\u0323c 3 c\u00e2y. M\u00f4\u0303i ng\u01b0\u01a1\u0300i trong \u0111\u00f4\u0323i 3 tr\u00f4\u0300ng \u0111\u01b0\u01a1\u0323c 4 c\u00e2y. S\u00f4\u0301 c\u00e2y ca\u0301c \u0111\u00f4\u0323i tr\u00f4\u0300ng \u0111\u01b0\u01a1\u0323c la\u0300 nh\u01b0 nhau. Ti\u0301nh s\u00f4\u0301 ng\u01b0\u01a1\u0300i \u01a1\u0309 m\u00f4\u0303i \u0111\u00f4\u0323i.<\/p>\n\n\n\n<p>Ba\u0300i 2: M\u00f4\u0323t khu v\u01b0\u01a1\u0300n hi\u0300nh ch\u01b0\u0303 nh\u00e2\u0323t co\u0301 chi\u00ea\u0300u da\u0300i va\u0300 chi\u00ea\u0300u r\u00f4\u0323ng ti\u0309 l\u00ea\u0323 v\u01a1\u0301i 9 va\u0300 7. Bi\u00ea\u0301t di\u00ea\u0323n ti\u0301ch cu\u0309a khu v\u01b0\u01a1\u0300n la\u0300 317m2. Ti\u0301nh chu vi khu v\u01b0\u01a1\u0300n hi\u0300nh ch\u01b0\u0303 nh\u00e2\u0323t.<\/p>\n\n\n\n<p>Ba\u0300i 3: 3 l\u01a1\u0301p 8A, 8B, 8C co\u0301 s\u00f4\u0301 ho\u0323c sinh gio\u0309i t\u01b0\u01a1ng \u01b0\u0301ng ti\u0309 l\u00ea\u0323 v\u01a1\u0301i 5, 4, 3. S\u00f4\u0301 ho\u0323c sinh gio\u0309i l\u01a1\u0301p 8A nhi\u00ea\u0300u h\u01a1n s\u00f4\u0301 ho\u0323c sinh gio\u0309i l\u01a1\u0301p 8B la\u0300 3 ho\u0323c sinh. Ho\u0309i m\u00f4\u0303i l\u01a1\u0301p co\u0301 bao nhi\u00eau ho\u0323c sinh?<\/p>\n\n\n\n<p>Ba\u0300i 4: Tr\u01b0\u01a1\u0300ng A co\u0301 3 l\u01a1\u0301p 7 bi\u00ea\u0301t 2\/3 ho\u0323c sinh l\u01a1\u0301p 7A1 b\u0103\u0300ng 3\/4 s\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A2. \u0110\u00f4\u0300ng th\u01a1\u0300i, 2\/3 s\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A1 b\u0103\u0300ng 4\/5 s\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A3. S\u00f4\u0301 ho\u0323c sinh cu\u0309a l\u01a1\u0301p 7A3 i\u0301t h\u01a1n t\u00f4\u0309ng s\u00f4\u0301 ho\u0323c sinh cu\u0309a 2 l\u01a1\u0301p kia la\u0300 57 em. Ti\u0301nh:<\/p>\n\n\n\n<p>a. S\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A1 la\u0300 bao nhi\u00eau?<\/p>\n\n\n\n<p>b. S\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A2 la\u0300 bao nhi\u00eau?<\/p>\n\n\n\n<p>c. S\u00f4\u0301 ho\u0323c sinh l\u01a1\u0301p 7A3 la\u0300 bao nhi\u00eau?<\/p>\n\n\n\n<p>Ba\u0300i 4: Tr\u00ean 3 ma\u0309nh ru\u00f4\u0323ng co\u0301 di\u00ea\u0323n ti\u0301ch b\u0103\u0300ng nhau co\u0301 3 \u0111\u00f4\u0323i cu\u0300ng th\u01b0\u0323c hi\u00ea\u0323n ca\u0300y. \u0110\u00f4\u0323i th\u01b0\u0301 nh\u00e2\u0301t ca\u0300y xong trong 3 nga\u0300y. \u0110\u00f4\u0323i th\u01b0\u0301 hai ca\u0300y nhanh h\u01a1n \u0111\u00f4\u0323i th\u01b0\u0301 nh\u00e2\u0301t 1 nga\u0300y. S\u00f4\u0301 nga\u0300y \u0111\u00f4\u0323i th\u01b0\u0301 3 ca\u0300y xong i\u0301t h\u01a1n t\u00f4\u0309ng s\u00f4\u0301 nga\u0300y hoa\u0300n tha\u0300nh cu\u0309a 2 \u0111\u00f4\u0323i la\u0300 2 nga\u0300y. Bi\u00ea\u0301t r\u0103\u0300ng t\u00f4\u0309ng s\u00f4\u0301 ma\u0301y ca\u0300y cu\u0309a 3 \u0111\u00f4\u0323i la\u0300 33 ma\u0301y. Ho\u0309i m\u00f4\u0303i \u0111\u00f4\u0323i co\u0301 bao nhi\u00eau ma\u0301y ca\u0300y?<\/p>\n\n\n\n<p>Bi\u0301 m\u00e2\u0323t Toa\u0301n ho\u0323c<\/p>\n\n\n\n<p>C\u00e2u chuy\u00ea\u0323n: \u201cChia bo\u0300 tro\u0300n s\u00f4\u0301\u201d<\/p>\n\n\n\n<p>Ta\u0323i m\u00f4\u0323t gia \u0111i\u0300nh \u00c2\u0301n \u0110\u00f4\u0323 no\u0323, Tr\u01b0\u01a1\u0301c khi m\u00e2\u0301t \u00f4ng b\u00f4\u0300 \u0111\u00ea\u0309 la\u0323i di chu\u0301c mu\u00f4\u0301n chia cho 3 ng\u01b0\u01a1\u0300i con trai 19 con bo\u0300. Trong di chu\u0301c vi\u00ea\u0301t: anh ca\u0309 se\u0303 nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c 1\/2 t\u00f4\u0309ng s\u00f4\u0301 bo\u0300. Anh th\u01b0\u0301 2 nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c 1\/4 t\u00f4\u0309ng s\u00f4\u0301 bo\u0300. Anh th\u01b0\u0301 3 nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c 1\/5 t\u00f4\u0309ng s\u00f4\u0301 bo\u0300. Theo t\u00f4n gia\u0301o cu\u0309a ng\u01b0\u01a1\u0300i \u00c2\u0301n, bo\u0300 la\u0300 th\u00e2\u0300n linh, \u0111\u00f4\u0323ng v\u00e2\u0323t linh thi\u00eang kh\u00f4ng \u0111\u01b0\u01a1\u0323c gi\u00ea\u0301t. V\u00e2\u0323y pha\u0309i chia s\u00f4\u0301 bo\u0300 nh\u01b0 th\u00ea\u0301 na\u0300o theo di chu\u0301c cu\u0309a ng\u01b0\u01a1\u0300i cha?<\/p>\n\n\n\n<p>Ly\u0301 gia\u0309i<\/p>\n\n\n\n<p>Vi\u0300 kh\u00f4ng bi\u00ea\u0301t chia th\u00ea\u0301 na\u0300o n\u00ean 3 ng\u01b0\u01a1\u0300i anh em \u0111a\u0303 nh\u01a1\u0300 quan to\u0300a chia h\u00f4\u0323. Tuy nhi\u00ean, to\u0300a cu\u0303ng kh\u00f4ng bi\u00ea\u0301t x\u01b0\u0309 ly\u0301 ra sao n\u00ean \u0111a\u0303 ba\u0309o r\u0103\u0300ng \u0111\u00e2y la\u0300 chuy\u00ea\u0323n gia \u0111i\u0300nh ca\u0301c anh v\u00ea\u0300 t\u01b0\u0323 gia\u0309i quy\u00ea\u0301t. M\u00f4\u0323t h\u00f4m no\u0323, co\u0301 m\u00f4\u0323t ng\u01b0\u01a1\u0300i th\u00f4ng mi\u0300nh \u0111\u00ea\u0301n va\u0300 giu\u0301p 3 anh em gia\u0309i quy\u00ea\u0301t v\u00e2\u0301n \u0111\u00ea\u0300 na\u0300y:<\/p>\n\n\n\n<p>Ng\u01b0\u01a1\u0300i th\u00f4ng minh na\u0300y \u0111a\u0303 cho th\u00eam 1 con bo\u0300 cu\u0309a mi\u0300nh va\u0300o t\u00f4\u0309ng s\u00f4\u0301 bo\u0300 cu\u0309a 3 anh em. Sau khi chia xong thi\u0300 3 anh em se\u0303 pha\u0309i tra\u0309 la\u0323i cho ng\u01b0\u01a1\u0300i na\u0300y 1 con bo\u0300. Nh\u01b0 v\u00e2\u0323y, t\u00f4\u0309ng s\u00f4\u0301 bo\u0300 hi\u00ea\u0323n ta\u0323i la\u0300 20 con.<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh ca\u0309 nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c la\u0300 20 x 1\/2 = 10 con bo\u0300<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh hai nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c la\u0300 20 x 1\/4 = 5 con bo\u0300<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh ba nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c la\u0300 20 x 1\/5 = 4 con bo\u0300<\/p>\n\n\n\n<p>Ta co\u0301: 20 \u2013 10 \u2013 5 \u2013 4 = 1 con bo\u0300. Ng\u01b0\u01a1\u0300i th\u00f4ng minh \u0111a\u0303 d\u0103\u0301t con bo\u0300 na\u0300y v\u00ea\u0300. Mo\u0323i ng\u01b0\u01a1\u0300i \u0111\u00ea\u0300u c\u00f4ng nh\u00e2\u0323n ca\u0301ch chia cu\u0309a anh na\u0300y r\u00e2\u0301t th\u00f4ng minh.<\/p>\n\n\n\n<p>C\u00e2u chuy\u00ea\u0323n 2<\/p>\n\n\n\n<p>Cu\u0300ng lu\u0301c \u0111o\u0301, co\u0301 ng\u01b0\u01a1\u0300i la\u0323i ba\u0309o; n\u00ea\u0301u nh\u01b0 ng\u01b0\u01a1\u0300i cha \u0111\u00ea\u0309 la\u0323i 15 con bo\u0300. Ng\u01b0\u01a1\u0300i anh th\u01b0\u0301 3 chi\u0309 \u0111\u01b0\u01a1\u0323c nh\u00e2\u0323n 1\/8 s\u00f4\u0301 bo\u0300 thi\u0300 ng\u01b0\u01a1\u0300i th\u00f4ng minh se\u0303 la\u0303i th\u00eam 1 con bo\u0300. Theo ba\u0323n ng\u01b0\u01a1\u0300i na\u0300y no\u0301i co\u0301 \u0111u\u0301ng kh\u00f4ng?<\/p>\n\n\n\n<p>C\u00e2u tra\u0309 l\u01a1\u0300i la\u0300 \u0111u\u0301ng b\u01a1\u0309i ng\u01b0\u01a1\u0300i cha \u0111\u00ea\u0309 la\u0323i 15 con. Anh th\u00f4ng minh th\u00eam va\u0300o 1 con. T\u00f4\u0309ng se\u0303 la\u0300 16 con.<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh ca\u0309 nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c lu\u0301c na\u0300y la\u0300 16 x 1\/2 = 8 con<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh hai nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c lu\u0301c na\u0300y la\u0300 16 x 1\/4 = 4 con<\/p>\n\n\n\n<p>S\u00f4\u0301 bo\u0300 anh ba nh\u00e2\u0323n \u0111\u01b0\u01a1\u0323c lu\u0301c na\u0300y la\u0300 16 x 1\/8 = 2 con<\/p>\n\n\n\n<p>Ta co\u0301: 16 \u2013 8 \u2013 4 \u2013 2 = 2 con. Nh\u01b0 v\u00e2\u0323y, anh th\u00f4ng minh kh\u00f4ng chi\u0309 d\u00e2\u0303n 1 con bo\u0300 cu\u0309a mi\u0300nh v\u00ea\u0300 ma\u0300 co\u0300n \u0111\u01b0\u01a1\u0323c th\u00eam 1 con bo\u0300 n\u01b0\u0303a.<\/p>\n\n\n\n<p>V\u00e2\u0301n \u0111\u00ea\u0300 chi\u0301nh xa\u0301c \u01a1\u0309 \u0111\u00e2y la\u0300: ti\u0309 l\u00ea\u0323 chia va\u0300 s\u00f4\u0301 bo\u0300 ng\u01b0\u01a1\u0300i cha \u0111\u00ea\u0309 la\u0323i.<\/p>\n\n\n\n<p>10 : 5 : 4 = 20 x 1\/2 : 20 x 1\/4 : 20 x 1\/5<\/p>\n\n\n\n<p>20 la\u0300 b\u00f4\u0323i s\u00f4\u0301 nho\u0309 nh\u00e2\u0301t cu\u0309a 10; 5; 4 v\u01b0\u0300a \u0111u\u0309 \u0111\u00ea\u0309 chia tro\u0300n s\u00f4\u0301 19.<\/p>\n\n\n\n<p>N\u00ea\u0301u mu\u00f4\u0301n chia s\u00f4\u0301 bo\u0300 cho ba anh em theo ti\u0309 l\u00ea\u0323 1\/2, 1\/4, 1\/8 thi\u0300 s\u00f4\u0301 bo\u0300 ng\u01b0\u01a1\u0300i cha c\u00e2\u0300n \u0111\u00ea\u0309 la\u0323i la\u0300 14 con \u0111\u00ea\u0309 anh th\u00f4ng minh kh\u00f4ng la\u0303i 1 con.<\/p>\n\n\n\n<p>4 : 2 : 1 = 8 x 1\/2 : 8 x 1\/4 : 8 x 1\/8<\/p>\n\n\n\n<p>L\u01a1\u0300i k\u00ea\u0301t<\/p>\n\n\n\n<p>Vietlearn hy vo\u0323ng ba\u0300i vi\u00ea\u0301t na\u0300y \u0111a\u0303 cung c\u00e2\u0301p ca\u0301c th\u00f4ng tin h\u01b0\u0303u i\u0301ch cho ca\u0301c ba\u0323n ho\u0323c sinh. Nrrsu ba\u0323n g\u0103\u0323p kho\u0301 kh\u0103n trong ho\u0323c t\u00e2\u0323p? Ha\u0303y nh\u01a1\u0301 ngay t\u01a1\u0301i Vietlearn. Vietlearn chi\u0301nh la\u0300 <a href=\"https:\/\/www.vietlearn.org\" data-internallinksmanager029f6b8e52c=\"2\" title=\"Vietlearn\" rel=\"nofollow\">gia s\u01b0<\/a> tr\u01b0\u0323c tuy\u00ea\u0301n s\u00f4\u0301 1 Vi\u00ea\u0323t Nam. V\u01a1\u0301i vi\u00ea\u0323c s\u01b0\u0309 du\u0323ng c\u00f4ng ngh\u00ea\u0323 AI \u0111\u00ea\u0309 ph\u00e2n ti\u0301ch, \u0111a\u0301nh gia\u0301 k\u00ea\u0301t qua\u0309 ho\u0323c t\u00e2\u0323p cu\u0309a t\u01b0\u0300ng ho\u0323c vi\u00ean. Tr\u00ean c\u01a1 s\u01a1\u0309 d\u01b0\u0303 li\u00ea\u0323u \u0111o\u0301, Vietlearn x\u00e2y d\u01b0\u0323ng l\u00f4\u0323 tri\u0300nh ho\u0323c t\u00e2\u0323p ca\u0301 nh\u00e2n ho\u0301a ri\u00eang bi\u00ea\u0323t. Nh\u01a1\u0300 v\u00e2\u0323y, Vietlearn t\u01b0\u0323 tin giu\u0301p ca\u0301c ba\u0323n ho\u0323c sinh ca\u0309i thi\u00ea\u0323n \u0111i\u00ea\u0309m s\u00f4\u0301 trong th\u01a1\u0300i gian ng\u0103\u0301n nh\u00e2\u0301t.<\/p>\n\n\n\n<p>H\u1ecdc t\u1ed1t l\u1edbp 7<\/p>\n\n\n\n<p>Hi\u00ea\u0323n nay, Vietlearn cung c\u00e2\u0301p kho\u0301a ho\u0323c tr\u01b0\u0323c tuy\u00ea\u0301n K12. Ca\u0301c ba\u0323n ho\u0323c sinh co\u0301 th\u00ea\u0309 ho\u0323c ngay ta\u0323i nha\u0300. Kho\u0301a ho\u0323c g\u00f4\u0300m ca\u0301c m\u00f4n: Ta\u0301n ho\u0323c, V\u00e2\u0323t ly\u0301, Ho\u0301a ho\u0323c, Ti\u00ea\u0301ng Anh da\u0300nh cho l\u01a1\u0301p 1 \u0111\u00ea\u0301n l\u01a1\u0301p 12. Tham kha\u0309o ngay kho\u0301a ho\u0323c cu\u0309a Vietlearn ta\u0323i \u0111\u00e2y.<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p>Phe\u0301p nh\u00e2n, chia s\u00f4\u0301 h\u01b0\u0303u ti\u0309 \u2013 Ho\u0323c Toa\u0301n 7 cu\u0300ng Vietlearn<\/p>\n\n\n\n<p>Ly\u0301 thuy\u00ea\u0301t v\u00e0 Ba\u0300i t\u00e2\u0323p c\u00f4\u0323ng tr\u01b0\u0300 s\u00f4\u0301 h\u01b0\u0303u ti\u0309 \u2013 Gi\u1ecfi to\u00e1n 7<\/p>\n\n\n\n<p>Ki\u00ea<\/p>\n\n\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>Ghi ch\u00fa: T\u00e0i li\u1ec7u tr\u00edch d\u1eabn \u01a0\u0309 ba\u0300i tr\u01b0\u01a1\u0301c, Vietlearn \u0111a\u0303 cu\u0300ng ca\u0301c ba\u0323n ho\u0323c sinh ti\u0300m hi\u00ea\u0309u ca\u0301c ki\u00ea\u0301n th\u01b0\u0301c v\u00ea\u0300 lu\u0303y th\u01b0\u0300a. V\u01a1\u0301i ba\u0300i vi\u00ea\u0301t na\u0300y, chu\u0301ng ta se\u0303 ti\u0300m hi\u00ea\u0309u ph\u00e2\u0300n ki\u00ea\u0301n th\u01b0\u0301c m\u01a1\u0301i. Trong ch\u01b0\u01a1ng tri\u0300nh Toa\u0301n 7, ca\u0301c ba\u0323n ho\u0323c sinh se\u0303 ti\u0300m hi\u00ea\u0309u v\u00ea\u0300 ti\u0309 l\u00ea\u0323 th\u01b0\u0301c. \u0110\u00e2y la\u0300 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[9,4],"tags":[],"class_list":["post-2643","post","type-post","status-publish","format-standard","hentry","category-toan-hoc","category-trung-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/2643","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=2643"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/2643\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=2643"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=2643"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=2643"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}