{"common":{"save":0,"post_id":"1389","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"981","post_id":"1389","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":10,"ques":"<span class='basic_left'>Kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a $40$ con l\u1ee3n \u0111\u01b0\u1ee3c ch\u1ecdn ng\u1eabu nhi\u00ean trong l\u00f4 th\u1eed nghi\u1ec7m (theo ph\u01b0\u01a1ng ph\u00e1p khoa h\u1ecdc) v\u00e0 l\u00f4 \u0111\u1ed1i ch\u1ee9ng (theo ph\u01b0\u01a1ng ph\u00e1p c\u0169) \u0111\u01b0\u1ee3c l\u00e0m tr\u00f2n \u0111\u1ebfn kg nh\u01b0 sau: <br\/> L\u00f4 th\u1eed nghi\u1ec7m <br\/> <table><tr><th>Gi\u00e1 tr\u1ecb $(x)$<\/th><th>121<\/th><th>128<\/th><th>130<\/th><th>135<\/th><th>138<\/th><th>140<\/th><th><\/th><\/tr><tr><td>T\u1ea7n s\u1ed1 $(n)$<\/td><td>2<\/td><td>3<\/td><td>6<\/td><td>4<\/td><td>3<\/td><td>2<\/td><td>$N=20$<\/td><\/tr><\/table> <br\/> L\u00f4 \u0111\u1ed1i ch\u1ee9ng <br\/> <table><tr><th>Gi\u00e1 tr\u1ecb $(x)$<\/th><th>120<\/th><th>123<\/th><th>128<\/th><th>130<\/th><th>133<\/th><th>135<\/th><th>140<\/th><th><\/th><\/tr><tr><td>T\u1ea7n s\u1ed1 $(n)$<\/td><td>2<\/td><td>3<\/td><td>4<\/td><td>5<\/td><td>3<\/td><td>2<\/td><td>1<\/td><td>$N=20$<\/td><\/tr><\/table> <br\/> Ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t \u0111\u1ec3 \u0111i\u1ec1n v\u00e0o ch\u1ed7 tr\u1ed1ng trong kh\u1eb3ng \u0111\u1ecbnh sau: <br\/> Tr\u1ecdng l\u01b0\u1ee3ng trung b\u00ecnh m\u1ed7i con l\u1ee3n \u1edf l\u00f4 th\u1eed nghi\u1ec7m so v\u1edbi l\u00f4 \u0111\u1ed1i ch\u1ee9ng _____ <\/span>","select":["A. T\u0103ng $3\\, kg$","B. Gi\u1ea3m $3\\, kg$","C. T\u0103ng $2\\, kg$ ","D. Gi\u1ea3m $2\\,kg$"],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>T\u00ednh s\u1ed1 trung b\u00ecnh c\u1ed9ng tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a m\u1ed7i con l\u1ee3n \u1edf t\u1eebng l\u00f4, sau \u0111\u00f3 so s\u00e1nh. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>L\u00f4 th\u1eed nghi\u1ec7m<br\/><table><tr><th>Gi\u00e1 tr\u1ecb $(x)$<\/th><th>121<\/th><th>128<\/th><th>130<\/th><th>135<\/th><th>138<\/th><th>140<\/th><th><\/th><\/tr><tr><td>T\u1ea7n s\u1ed1 $(n)$<\/td><td>2<\/td><td>3<\/td><td>6<\/td><td>4<\/td><td>3<\/td><td>2<\/td><td>$N=20$<\/td><\/tr><tr><td>C\u00e1c t\u00edch $(x.n)$<\/td><td>242<\/td><td>384<\/td><td>780<\/td><td>540<\/td><td>414<\/td><td>280<\/td><td>T\u1ed5ng: 2640<\/td><\/tr><\/table> <br\/> $\\Rightarrow \\overline{{{X}_{1}}}=\\dfrac{2640}{20}=132$ (kg) (1) <br\/> L\u00f4 \u0111\u1ed1i ch\u1ee9ng <table><tr><th>Gi\u00e1 tr\u1ecb $(x)$<\/th><th>120<\/th><th>123<\/th><th>128<\/th><th>130<\/th><th>133<\/th><th>135<\/th><th>140<\/th><th><\/th><\/tr><tr><td>T\u1ea7n s\u1ed1 $(n)$<\/td><td>2<\/td><td>3<\/td><td>4<\/td><td>5<\/td><td>3<\/td><td>2<\/td><td>1<\/td><td>$N=20$<\/td><\/tr><tr><td>C\u00e1c t\u00edch $(x.n)$<\/td><td>240<\/td><td>369<\/td><td>512<\/td><td>650<\/td><td>399<\/td><td>270<\/td><td>140<\/td><td>T\u1ed5ng: $2580$<\/td><\/tr><\/table> <br\/> $\\Rightarrow \\overline{{{X}_{2}}}=\\dfrac{2580}{20}=129$ (kg) (2) <br\/> T\u1eeb (1) v\u00e0 (2) ta th\u1ea5y tr\u1ecdng l\u01b0\u1ee3ng trung b\u00ecnh m\u1ed7i con l\u1ee3n \u1edf l\u00f4 th\u1eed nghi\u1ec7m so v\u1edbi l\u00f4 \u0111\u1ed1i ch\u1ee9ng t\u0103ng $3\\,kg.$ <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 A.<\/span> <\/span>","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:54"},{"id":"982","post_id":"1389","mon_id":"0","chapter_id":"0","question":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","options":{"time":24,"part":[{"title":"\u0110i\u1ec1n k\u1ebft qu\u1ea3 \u0111\u00fang nh\u1ea5t v\u00e0o \u00f4 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["14,5","14.5"]]],"list":[{"point":10,"width":40,"content":"","type_input":"","ques":" <span class='basic_left'> Trung b\u00ecnh c\u1ed9ng c\u1ee7a $24$ s\u1ed1 l\u00e0 $15.$ N\u1ebfu lo\u1ea1i \u0111i hai s\u1ed1 $20$ v\u00e0 $21$ th\u00ec trung b\u00ecnh c\u1ed9ng c\u1ee7a c\u00e1c s\u1ed1 c\u00f2n l\u1ea1i b\u1eb1ng bao nhi\u00eau? <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> _input_ <\/span>","explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>T\u00ednh t\u1ed5ng c\u1ee7a $22$ s\u1ed1 c\u00f2n l\u1ea1i (sau khi b\u1ecf hai s\u1ed1 $20$ v\u00e0 $21$) <br\/> T\u00ednh s\u1ed1 trung b\u00ecnh c\u1ee7a $22$ s\u1ed1 c\u00f2n l\u1ea1i \u0111\u00f3. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>Trung b\u00ecnh c\u1ed9ng c\u1ee7a $24$ s\u1ed1 l\u00e0 $15$ th\u00ec t\u1ed5ng c\u1ee7a $24$ s\u1ed1 l\u00e0: $24.15=360$ <br\/> T\u1ed5ng c\u1ee7a $22$ s\u1ed1 (sau khi lo\u1ea1i hai s\u1ed1 $20$ v\u00e0 $21$) l\u00e0: <br\/> $360-20-21=319$ <br\/> S\u1ed1 trung b\u00ecnh c\u1ed9ng c\u1ee7a $22$ s\u1ed1 c\u00f2n l\u1ea1i l\u00e0: <br\/> $\\dfrac{319}{22}=14,5$ <br\/> <span class='basic_pink'> V\u1eady s\u1ed1 c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0 $14,5$<\/span><\/span>"}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:54"},{"id":"983","post_id":"1389","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":10,"ques":"<span class='basic_left'>H\u1ecdc sinh l\u1edbp $7A$ tr\u01b0\u1eddng Trung h\u1ecdc c\u01a1 s\u1edf Nguy\u1ec5n Tr\u00e3i \u0111\u01b0\u1ee3c ph\u00e2n lo\u1ea1i v\u1ec1 h\u1ecdc l\u1ef1c nh\u01b0 sau: $20\\%$ lo\u1ea1i gi\u1ecfi, $25\\%$ lo\u1ea1i kh\u00e1, $50\\%$ lo\u1ea1i trung b\u00ecnh, $5\\%$ lo\u1ea1i y\u1ebfu. <br\/> Ta c\u00f3 bi\u1ec3u \u0111\u1ed3 h\u00ecnh qu\u1ea1t bi\u1ec3u di\u1ec5n s\u1ef1 ph\u00e2n lo\u1ea1i theo d\u1eef ki\u1ec7n tr\u00ean l\u00e0: <center><img src='img\/D7B22K1_7.png' \/><\/center> <\/span>","select":["\u0110\u00fang","Sai"],"explain":"<span class='basic_left'><span class='basic_green'>H\u01b0\u1edbng d\u1eabn:<\/span><br\/>Ta ki\u1ec3m tra c\u00e1c v\u1ea5n \u0111\u1ec1 sau: <br\/> - C\u00e1c v\u00f9ng \u0111\u00e1nh d\u1ea5u s\u1ed1 ph\u1ea7n tr\u0103m x\u1ebfp lo\u1ea1i h\u1ecdc l\u1ef1c c\u1ee7a h\u1ecdc sinh trong bi\u1ec3u \u0111\u1ed3 c\u00f3 \u0111\u00fang kh\u00f4ng. <br\/> - S\u1ed1 \u0111o g\u00f3c \u1edf t\u00e2m c\u00f3 t\u01b0\u01a1ng \u1ee9ng v\u1edbi s\u1ed1 ph\u1ea7n tr\u0103m x\u1ebfp lo\u1ea1i h\u1ecdc l\u1ef1c kh\u00f4ng. <br\/> <span class='basic_green'>B\u00e0i gi\u1ea3i:<\/span><br\/>T\u1eeb s\u1ed1 li\u1ec7u \u0111\u00e3 cho, ta c\u00f3 th\u1ec3 bi\u1ec3u di\u1ec5n b\u1eb1ng bi\u1ec3u \u0111\u1ed3 h\u00ecnh qu\u1ea1t nh\u01b0 sau: <br\/> - D\u1ef1ng h\u00ecnh tr\u00f2n c\u00f3 b\u00e1n k\u00ednh t\u1ef1 ch\u1ecdn <br\/> - H\u00ecnh tr\u00f2n n\u00e0y \u0111\u01b0\u1ee3c chia th\u00e0nh c\u00e1c h\u00ecnh qu\u1ea1t m\u00e0 g\u00f3c \u1edf t\u00e2m c\u1ee7a h\u00ecnh qu\u1ea1t t\u1ec9 l\u1ec7 v\u1edbi t\u1ea7n su\u1ea5t (ph\u1ea7n tr\u0103m lo\u1ea1i h\u1ecdc sinh) <br\/> $20\\%$ lo\u1ea1i gi\u1ecfi th\u00ec g\u00f3c \u1edf t\u00e2m l\u00e0: $20\\%{{.360}^{o}}=\\dfrac{20}{100}{{.360}^{o}}={{72}^{o}}$ <br\/> T\u01b0\u01a1ng t\u1ef1, $25\\%$ lo\u1ea1i kh\u00e1 th\u00ec g\u00f3c \u1edf t\u00e2m l\u00e0: $90^o$ <br\/> $50\\%$ lo\u1ea1i trung b\u00ecnh th\u00ec g\u00f3c \u1edf t\u00e2m l\u00e0: $180^o$ <br\/> $5\\%$ lo\u1ea1i y\u1ebfu th\u00ec g\u00f3c \u1edf t\u00e2m l\u00e0: $18^o$ <br\/> Do \u0111\u00f3, bi\u1ec3u \u0111\u1ed3 h\u00ecnh qu\u1ea1t trong \u0111\u1ec1 b\u00e0i ho\u00e0n to\u00e0n \u0111\u00fang v\u1edbi s\u1ed1 li\u1ec7u \u0111\u00e3 cho. <br\/><span class='basic_pink'> V\u1eady \u0111\u00e1p \u00e1n l\u00e0 \u0110\u00fang.<\/span> <br\/> <b> L\u01b0u \u00fd: <\/b> <i> \u0110\u1ed1i v\u1edbi c\u00e1c b\u00e0i v\u1ebd bi\u1ec3u \u0111\u1ed3 h\u00ecnh qu\u1ea1t v\u1edbi c\u00e1c s\u1ed1 li\u1ec7u \u0111\u00e3 cho tr\u01b0\u1edbc, ta l\u00e0m nh\u01b0 sau: <br\/> + D\u1ef1ng h\u00ecnh tr\u00f2n c\u00f3 b\u00e1n k\u00ednh t\u1ef1 ch\u1ecdn <br\/> + X\u00e1c \u0111\u1ecbnh s\u1ed1 ph\u1ea7n tr\u0103m c\u1ee7a t\u1eebng \u0111\u1ed1i t\u01b0\u1ee3ng \u0111\u01b0\u1ee3c x\u00e9t <br\/> + T\u00ednh s\u1ed1 \u0111o g\u00f3c \u1edf t\u00e2m theo t\u1eebng s\u1ed1 ph\u1ea7n tr\u0103m c\u1ee7a t\u1eebng \u0111\u1ed1i t\u01b0\u1ee3ng \u0111\u00f3. <br\/> C\u00f4ng th\u1ee9c t\u00ednh g\u00f3c \u1edf t\u00e2m nh\u01b0 sau: (S\u1ed1 ph\u1ea7n tr\u0103m) $\\times 360^o$ <\/i> <\/span>","column":2}]}]},"correct":"","level":"3","hint":"","answer":"","type":"json","extra_type":"","time":"0","user_id":"0","test":"0","date":"2019-09-30 09:22:54"}]}