a , -1,8+(1+4/5) b , 11/21+5/6÷6/8-5/6.6/7 c , -3/8.16.8/17-0,375.79/17 d , (-1/2)÷1/3/8-25% [-6/2/11]

0 bình luận về “a , -1,8+(1+4/5) b , 11/21+5/6÷6/8-5/6.6/7 c , -3/8.16.8/17-0,375.79/17 d , (-1/2)÷1/3/8-25% [-6/2/11]”

1. a , -1,8+(1+4/5)

   = -9/5 + 9/5 =0

   b , 11/21+5/6÷6/8-5/6.6/7 

   =11/21+5/6 : 6/8-5/6 : 7/6

   =11/21 + 5/6 : (6/8 – 7/6)

   =11/21 + 5/6 : (-5/12)

   =11/21 + (-2)

   = -31/21

   c , -3/8.16.8/17-0,375.79/17

   =-3/8 . 16 . 8/17 – 3/8 . 79/17

   =-3/8 . 128/17 – 3/8 . 79/17

   =3/8 . (-128/17) – 3/8 . 79/17

   =3/8 . (-128/17 – 79/17)

   =3/8 . (-207/17)

   =-621/136

   d , (-1/2)÷1/3/8-25% [-6/2/11]

   =-1/2 : 11/8 – 1/4 . (-68/11)

   =-4/11 – (-17/11)

   =13/11

   Trả lời

2. Đáp án:

   `a)`

   ` -1,8 + (1+ \frac{4}{5}) = -1,8 + ( 1 + 0,8)`

   ` = -1,8 + 1,8`

   ` = 0`

   `b)`

   `\frac{11}{21} + \frac{5}{6} : \frac{6}{8} – \frac{5}{6}. \frac{6}{7}`

   ` = \frac{11}{21} + \frac{10}{9} – \frac{5}{7}`

   ` = \frac{103}{63} – \frac{5}{7}`

   ` = \frac{58}{63}`

   `c)`

   `\frac{-3}{8}.16.\frac{8}{17} – 0,375. \frac{79}{17}`

   ` = \frac{-3}{18}. \frac{128}{17} + \frac{-3}{8}. \frac{79}{17}`

   ` = \frac{-3}{18}. (\frac{128}{17} + \frac{-273}{136})`

   ` = \frac{-3}{18}. \frac{787}{136}`

   ` =\frac{-787}{816}`

   `d)`

   ` \frac{-1}{2}: 1\frac{3}{8} – 25%. (-6\frac{2}{11})`

   ` = \frac{-1}{2} : \frac{11}{8} – \frac{1}{4}. \frac{-68}{11}`

   ` = \frac{-11}{16} – \frac{-17}{11}`

   ` = \frac{17}{16}`

    

   Trả lời