{"common":{"save":0,"post_id":"8906","level":3,"total":10,"point":10,"point_extra":0},"segment":[{"id":"4779","post_id":"8906","mon_id":"1159414","chapter_id":"1159498","question":"<p>\u0110\u1ed5i 10,8 km\/h = <input class=\"_tit_hoi\" disabled=\"disabled\" type=\"text\"\/> m\/s.<\/p>","options":["<strong>A.<\/strong> 30 m\/s","<strong>B.<\/strong> 3 m\/s","<strong>C.<\/strong> 2 m\/s","<strong>D.<\/strong> 20 m\/s"],"correct":"2","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>B.<\/strong> 3 m\/s.<\/span><\/p><p>10,8 km\/h = (10 800 : 3600) m\/s = 3 m\/s.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2025-04-17 08:53:03","option_type":"txt","len":0},{"id":"4782","post_id":"8906","mon_id":"1159414","chapter_id":"1159498","question":"<p>An \u0111i b\u1ed9 t\u1eeb nhà lúc 7 gi\u1edd 30 phút và \u0111\u1ebfn th\u01b0 vi\u1ec7n lúc 7 gi\u1edd 45 phút. Bi\u1ebft quãng \u0111\u01b0\u1eddng t\u1eeb nhà An \u0111\u1ebfn th\u01b0 vi\u1ec7n là 675 m. Tính v\u1eadn t\u1ed1c c\u1ee7a An theo \u0111\u01a1n v\u1ecb m\/s.<\/p>","options":["<strong>A.<\/strong> 0,75 m\/s","<strong>B.<\/strong> 0,9 m\/s","<strong>C.<\/strong> 0,8 m\/s","<strong>D.<\/strong> 0,85 m\/s"],"correct":"1","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>A.<\/strong> 0,75 m\/s.<\/span><\/p><p>Th\u1eddi gian An \u0111i t\u1eeb nhà \u0111\u1ebfn th\u01b0 vi\u1ec7n là <\/p><p>7 gi\u1edd 45 phút – 7 gi\u1edd 30 phút = 15 phút = 900 giây.<\/p><p>V\u1eadn t\u1ed1c c\u1ee7a An là<\/p><p>675 : 900 = 0,75 m\/s.<\/p><p>\u0110áp s\u1ed1 0,75 m\/s.<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2025-04-17 08:56:18","option_type":"txt","len":1},{"id":"4784","post_id":"8906","mon_id":"1159414","chapter_id":"1159498","question":"<p>M\u1ed9t con báo \u0111\u1ed1m khi c\u1ea7n có th\u1ec3 ch\u1ea1y \u0111\u01b0\u1ee3c 27 km trong vòng 20 phút. Tính t\u1ed1c \u0111\u1ed9 c\u1ee7a báo \u0111\u1ed1m theo \u0111\u01a1n v\u1ecb km\/h và m\/s.<\/p>","options":["<strong>A.<\/strong> 225 km\/h ; 8,1 m\/s","<strong>B.<\/strong> 22,5 km\/h ; 81 m\/s","<strong>C.<\/strong> 81 km\/h ; 22,5 m\/s","<strong>D.<\/strong> 8,1 km\/h ; 225 m\/s"],"correct":"3","level":"3","hint":"","answer":"<p>Ch\u1ecdn <span style=\"color:#16a085;\"><strong>C.<\/strong> 81 km\/h ; 22,5 m\/s.<\/span><\/p><p>\u0110\u1ed5i 20 phút = <span class=\"math-tex\">$\\dfrac{1}{3}$<\/span> h.<\/p><p>V\u1eadn t\u1ed1c c\u1ee7a báo \u0111\u1ed1m là <\/p><p>27 : <span class=\"math-tex\">$\\dfrac{1}{3}$<\/span> = 27 x 3 = 81 km\/h.<\/p><p>\u0110\u1ed5i 81 km\/h = (81 000 : 3600) m\/s = 22,5 m\/s.<\/p><p>\u0110áp s\u1ed1: <span style=\"color:#16a085;\">81 km\/h;<br \/> 22,5 m\/s.<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"0","date":"2025-04-17 09:01:55","option_type":"txt","len":2}]}
