Question

Answer 1

`7/9+5/12-3/4`

`=28/36 + 15/36 - 27/36`

`=(28+15-27)/36`

`=16/36`

`=4/9`

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`1,4 . 15/49 - (4/5+2/3): 2 1/5`

`=7/5 . 15/49 - (12/15 + 10/15) : 11/5`

`=7/5 . 15/49 - 22/15 : 11/5`

`=7/5 . 15/49 - 22/15 . 5/11`

`=7/16 - 2/3`

`=-5/21`

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`6/7 + 5/7 : 5-8/9`

`=6/7 + 5/7 . 5 - 8/9`

`=6/7 + 1/7 - 8/9`

`=7/7 - 8/9`

`=1-8/9`

`=9/9-8/9`

`=1/9`

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`(7/8-3/4). 1/3 - 7/2 : 5 1/4`

`=(7/8-6/8) . 1/3 - 7/2 : 21/4`

`=1/8 . 1/3 - 7/2 . 4/21`

`=1/6 - 2/3`

`=1/6 - 4/6`

`=-1/2`

Answer 2

a: \(=\dfrac{28}{36}+\dfrac{15}{36}-\dfrac{27}{36}=\dfrac{16}{36}=\dfrac{4}{9}\)

b: \(=\dfrac{7}{5}\cdot\dfrac{15}{49}-\dfrac{22}{15}:\dfrac{11}{5}\)

\(=\dfrac{3}{7}-\dfrac{2}{3}=\dfrac{-5}{21}\)