Thực hiện phép tính A)25/42-20/63 B)9/50-13/75-1/6 C)2/15-2/65-4/39

Đáp án:

`a)` `25/42-20/63`

`=75/126-40/126`

`=(75-40)/126`

`=35/126`

`=5/18`

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`b,` `9/50 - 13/75 -1/6`

`= 27/150 - 26/150 - 25/150 `

`= (27 - 26 - 25)/150`

`= (-24)/150`

`=  (-4)/25`

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`c,` `2/15 - 2/65 - 4/39`

`= (2/15 - 4/39) - 2/65`

`= 2/65 - 2/65` `

`= (2 - 2)/65`

`= 0/65`

`= 0`

`#dariana`