Tính toán với số thập phân - Bài tập dễ số 2

Home Toán lớp 6 (Sách KNTT)Toán lớp 6 Tập 2 Bài 29: Tính toán với số thập phânBài tập cơ bản

{"common":{"save":0,"post_id":"4805","level":1,"total":10,"point":10,"point_extra":0},"segment":[{"id":"8251","post_id":"4805","mon_id":"1158113","chapter_id":"1158126","question":"Ch\u1ecdn phép tính cho k\u1ebft qu\u1ea3 \u0111úng<\/strong><\/p>","options":["A.<\/strong> 3,256 + 4,264 = 7,52","B. <\/strong>(-2,18) + (-2,32) = 4,5"],"correct":"1","level":"1","hint":"- Mu\u1ed1n c\u1ed9ng hai s\u1ed1 th\u1eadp phân âm, ta c\u1ed9ng hai s\u1ed1 \u0111\u1ed1i c\u1ee7a chúng r\u1ed3i thêm d\u1ea5u tr\u1eeb tr\u01b0\u1edbc k\u1ebft qu\u1ea3.<\/p>- Mu\u1ed1n c\u1ed9ng hai s\u1ed1 th\u1eadp phân trái d\u1ea5u<\/strong> ta làm nh\u01b0 sau:<\/p>    + L\u1ea5y s\u1ed1 d\u01b0\u01a1ng tr\u1eeb cho s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm<\/strong> n\u1ebfu s\u1ed1 d\u01b0\u01a1ng l\u1edbn h\u01a1n ho\u1eb7c b\u1eb1ng s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm<\/strong>.<\/p>    + L\u1ea5y s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm tr\u1eeb cho s\u1ed1 d\u01b0\u01a1ng<\/strong> và \u0111\u1eb7t d\u1ea5u tr\u1eeb tr\u01b0\u1edbc k\u1ebft qu\u1ea3<\/strong> n\u1ebfu s\u1ed1 d\u01b0\u01a1ng nh\u1ecf h\u01a1n s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm<\/strong> <\/p>","answer":"A.<\/strong> 3,256 + 4,264 = 7,52 (\u0111úng<\/span>)<\/p>B. <\/strong>-2,18 + (-2,32) = 4,5 (sai <\/span>vì  (-2,18) + (-2,32) = -(2,18 + 2,32) = -4,5 )<\/p>\u0110áp án \u0111úng là    A.<\/strong> 3,256 + 4,264 = 7,52<\/span><\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"1","date":"2021-10-04 03:07:06","option_type":"txt","len":2},{"id":"8252","post_id":"4805","mon_id":"1158113","chapter_id":"1158126","question":"Ch\u1ecdn phép tính cho k\u1ebft qu\u1ea3 sai<\/strong><\/p>","options":["A. <\/strong>3,56 + (-4,66) = 1,1","B.<\/strong> (-1,52) + 2,82 = 1,3"],"correct":"1","level":"1","hint":"- Mu\u1ed1n c\u1ed9ng hai s\u1ed1 th\u1eadp phân âm, ta c\u1ed9ng hai s\u1ed1 \u0111\u1ed1i c\u1ee7a chúng r\u1ed3i thêm d\u1ea5u tr\u1eeb tr\u01b0\u1edbc k\u1ebft qu\u1ea3.<\/p>- Mu\u1ed1n c\u1ed9ng hai s\u1ed1 th\u1eadp phân trái d\u1ea5u ta làm nh\u01b0 sau:<\/p>    + L\u1ea5y s\u1ed1 d\u01b0\u01a1ng tr\u1eeb cho s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm n\u1ebfu s\u1ed1 d\u01b0\u01a1ng l\u1edbn h\u01a1n ho\u1eb7c b\u1eb1ng s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm.<\/p>    + L\u1ea5y s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm tr\u1eeb cho s\u1ed1 d\u01b0\u01a1ng và \u0111\u1eb7t d\u1ea5u tr\u1eeb tr\u01b0\u1edbc k\u1ebft qu\u1ea3 n\u1ebfu s\u1ed1 d\u01b0\u01a1ng nh\u1ecf h\u01a1n s\u1ed1 \u0111\u1ed1i c\u1ee7a s\u1ed1 âm <\/p>","answer":"A. <\/strong>3,56 + (-4,66) = 1,1   (<\/span>sai<\/strong><\/span> <\/span>vì  3,56 + (-4,66) = -(4,66 - 3,56) = -1,1<\/strong> )<\/p>B.<\/strong> (-1,52) + 2,82 = 1,3   (\u0111úng<\/span><\/strong> vì   <\/b>(-1,52) + 2,82 = 2,82 - 1,52 = 1,3 )<\/p>\u0110áp án c\u1ea7n ch\u1ecdn là  A. 3,56 + (-4,66) = 1,1 <\/span> (\u0111\u1ec1 yêu c\u1ea7u ch\u1ecdn phép tính cho k\u1ebft qu\u1ea3 sai<\/strong><\/span>)<\/p>","type":"choose","extra_type":"classic","time":"0","user_id":"131","test":"3","date":"2021-10-04 03:07:42","option_type":"txt","len":2},{"id":"8255","post_id":"4805","mon_id":"1158113","chapter_id":"1158126","question":"Tính  5,285 - (-3,145)<\/p>","options":["-8,43","8,43","-2,14","2,14"],"correct":"2","level":"1","hint":"Cho a và b là hai s\u1ed1 th\u1eadp phân thì   a - b = a + (-b)<\/strong><\/p>","answer":"Ta có:  5,285 - (-3,145) = 5,285 + 3,145 = 8,43<\/p>\u0110áp án \u0111úng là   8,43<\/strong><\/span><\/p>","type":"choose","extra_type":"shape1","time":"0","user_id":"131","test":"1","date":"2021-10-04 03:21:05","option_type":"txt","len":0}]}