{"common":{"save":0,"post_id":"6709","level":2,"total":10,"point":10,"point_extra":0},"segment":[{"id":"7331","mon_id":"1158769","chapter_id":"1158999","post_id":"6709","question":"<p>Trong h\u1ed9p có 5 qu\u1ea3 c\u1ea7u màu \u0111\u1ecf và 7 qu\u1ea3 c\u1ea7u màu xanh có kích th\u01b0\u1edbc và hình d\u1ea1ng nh\u01b0 nhau. L\u1ea5y ng\u1eabu nhiên 5 qu\u1ea3 c\u1ea7u t\u1eeb h\u1ed9p. H\u1ecfi có bao nhiêu kh\u1ea3 n\u0103ng l\u1ea5y \u0111\u01b0\u1ee3c s\u1ed1 qu\u1ea3 c\u1ea7u \u0111\u1ecf nhi\u1ec1u h\u01a1n s\u1ed1 qu\u1ea3 c\u1ea7u xanh?<\/p>","options":["<strong>A.<\/strong> 245","<strong>B.<\/strong> 3480","<strong>C.<\/strong> 246","<strong>D.<\/strong> 3360"],"correct":"3","level":"0","hint":"","answer":"<p>L\u1ea5y ng\u1eabu nhiên 5 qu\u1ea3 c\u1ea7u t\u1eeb h\u1ed9p 12 qu\u1ea3 c\u1ea7u, \u0111\u1ec3 s\u1ed1 qu\u1ea3 c\u1ea7u \u0111\u1ecf nhi\u1ec1u h\u01a1n s\u1ed1 qu\u1ea3 c\u1ea7u xanh, có nh\u0169ng tr\u01b0\u1eddng h\u1ee3p x\u1ea3y ra là:<\/p><p>+ Tr\u01b0\u1eddng h\u1ee3p 1: l\u1ea5y 5 qu\u1ea3 c\u1ea7u \u0111\u1ecf,<\/p><p> có <span class=\"math-tex\">$C_5^5$<\/span><strong> = 1<\/strong> kh\u1ea3 n\u0103ng.<\/p><p>+ Tr\u01b0\u1eddng h\u1ee3p 2: l\u1ea5y 4 qu\u1ea3 c\u1ea7u \u0111\u1ecf và 1 qu\u1ea3 c\u1ea7u xanh<\/p><p> có <span class=\"math-tex\">$C_5^4.C_7^1$<\/span> <strong>= 35<\/strong> kh\u1ea3 n\u0103ng.<\/p><p>+ Tr\u01b0\u1eddng h\u1ee3p 3: l\u1ea5y 3 qu\u1ea3 c\u1ea7u \u0111\u1ecf và 2 qu\u1ea3 c\u1ea7u xanh<\/p><p> có <span class=\"math-tex\">$C_5^3.C_7^2$<\/span> <strong>= 210<\/strong> kh\u1ea3 n\u0103ng.<\/p><p>Theo quy t\u1eafc c\u1ed9ng, có 1 + 35 + 210 = 246 kh\u1ea3 n\u0103ng<\/p><p>Ch\u1ecdn<span style=\"color:#16a085;\"> <strong>C.<\/strong> 246<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-09-24 02:23:36","option_type":"txt","len":0},{"id":"7334","mon_id":"1158769","chapter_id":"1158999","post_id":"6709","question":"<p>S\u1eafp x\u1ebfp 5 b\u1ea1n C\u01b0\u1eddng, H\u1ed3ng, Hoa, Nam, Mai vào m\u1ed9t chi\u1ebfc gh\u1ebf dài có 5 ch\u1ed7 ng\u1ed3i. H\u1ecfi có bao nhiêu cách x\u1ebfp sao cho b\u1ea1n C\u01b0\u1eddng và b\u1ea1n Nam không ng\u1ed3i c\u1ea1nh nhau?<\/p>","options":["<strong>A.<\/strong> 100","<strong>B.<\/strong> 72","<strong>C.<\/strong> 104","<strong>D.<\/strong> 108"],"correct":"2","level":"0","hint":"","answer":"<p>Có 5! = <strong>120<\/strong> cách x\u1ebfp 5 b\u1ea1n ng\u1ed3i b\u1ea5t kì.<\/p><p>Có 2 cách x\u1ebfp hai b\u1ea1n C\u01b0\u1eddng và Nam ng\u1ed3i c\u1ea1nh nhau. V\u1edbi m\u1ed7i cách, có 4! cách x\u1ebfp hai b\u1ea1n \u0111ó và ba b\u1ea1n còn l\u1ea1i vào 5 ch\u1ed7 ng\u1ed3i. Do \u0111ó có 2 . 4! = <strong>48<\/strong> cách x\u1ebfp chõ ng\u1ed3i cho 5 b\u1ea1n mà C\u01b0\u1eddng và Nam ng\u1ed3i c\u1ea1nh nhau.<\/p><p>V\u1eady có 120 – 48 = 72 cách x\u1ebfp sao cho C\u01b0\u1eddng và Nam không ng\u1ed3i c\u1ea1nh nhau.<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 72<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-09-24 02:38:55","option_type":"txt","len":0},{"id":"7335","mon_id":"1158769","chapter_id":"1158999","post_id":"6709","question":"<p>T\u1eeb các ch\u1eef s\u1ed1 c\u1ee7a t\u1eadp h\u1ee3p A = {0; 1; 2; 3; 4; 5; 6} l\u1eadp \u0111\u01b0\u1ee3c bao nhiêu s\u1ed1 t\u1ef1 nhiên g\u1ed3m 4 ch\u1eef s\u1ed1 \u0111ôi m\u1ed9t khác nhau?<\/p>","options":["<strong>A.<\/strong> 418","<strong>B.<\/strong> 720","<strong>C.<\/strong> 300","<strong>D.<\/strong> 731"],"correct":"2","level":"0","hint":"","answer":"<p>G\u1ecdi s\u1ed1 c\u1ea7n tìm có d\u1ea1ng <span class=\"math-tex\">$\\overline{abcd}$<\/span>.<\/p><p>a có <span style=\"color:#16a085;\"><strong>6<\/strong> <\/span>cách ch\u1ecdn.<\/p><p>Ch\u1ecdn b, c, d có <span style=\"color:#16a085;\"><span class=\"math-tex\">$A_6^3$<\/span><\/span> cách.<\/p><p>V\u1eady l\u1eadp \u0111\u01b0\u1ee3c <span style=\"color:#16a085;\"><strong>6 . <span class=\"math-tex\">$A_6^3$<\/span> = 720<\/strong><\/span> s\u1ed1.<\/p><p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 720<\/span><\/p>","type":"choose","extra_type":"classic","user_id":"131","test":"0","date":"2023-09-24 02:42:34","option_type":"txt","len":0}]}