Các bạn có thể giúp mình làm bài này này được không rõ rất cảm ơn

$\text{a.Phép cộng}$

`3/4` `+` `5/4` `=` `8/4` `=` `2`

`3/8` `+` `7/3` `=` `9/24` `+` `56/24` `=` `65/24`

`2/3` `+` `3/4` `=` `8/12` `+` `9/12` `=` `17/12`

`9/4` `+` `3/5` `=` `45/20` `+` `12/20` `=` `59/20`

`4/24` `+` `1/4` `=` `4/24` `+` `6/24` `=` `5/12`

`26/81` `+``4/27` `=` `26/81` `+` `12/81` `=` `38/81` 

$\text{b.Phép trừ}$

`8/3` `-` `5/3` `=` `3/3` `=` `1`

`16/5` `-` `9/5` `=` `5/5` `=` `1`

`3/15` `-` `5/35` `=` `21/105` `-``15/105` `=` `6/105`

`18/27` `-` `2/6`` =` `18/27` `-` `1/3` `=` `18/27` `-` `9/27` `=` `1/3`

`37/12` `-` `3` `=` `37/12` `-` `36/12` `=` `1/12`

`5` `-` `14/3` `=` `15/3``-` `14/3` `=` `1/3`

$\text{c.Phép nhân}$

`4/5` `×` ` 6/7` `=` `24/35`

`2/4` `×` `7/5` `=` `7/10`

`11/9``×` `5/10` `=` `11/18`

`7/13` `×` `13/7` `=` `91/91` `=` `1`

`4` `×`` 6/7` `=` `24/7`

`3` `×` `4/11` `=` `12/11`

`3/9` `×` `6/8``=``18/72` `=` `1/4`

3/4 + 5/4 = 8/4 = 2

3/8 + 7/3 = 9/24 + 56/24 = 65/24

2/3 + 3/4 = 8/12 + 9/12 = 17/12

9/4 + 3/5 = 45/20 + 12/20 = 59/20

4/24 + 1/4 = 4/24 + 6/24 = 5/12

26/81 + 4/27 = 26/81 + 12/81 = 38/81

8/3 - 5/3 = 3/3 = 1

16/5 - 9/5 = 5/5 = 1

3/15 - 5/35 = 21/105 - 15/105 = 6/105

18/27 - 2/6 = 18/27 - 1/3 = 18/27 - 9/27 = 1/3

37/12 - 3 = 37/12 - 36/12 = 1/12

5 - 14/3 = 15/3 - 14/3 = 1/3

4/5 × 6/7 = 24/35

2/4 × 7/5 = 7/10

11/9 × 5/10 = 11/18

7/13 × 13/7 = 91/91 = 1

4 × 6/7 = 24/7

3 × 4/11 = 12/11

3/9 × 6/8 = 1/4