9/12 +7/12 5/7+1/7+3/7 16/25+9/25

`9/12` `+` `7/12` `=` `\frac{9 + 7}{12}` `=` `16/12` `=` `4/3`.

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`5/7` `+` `1/7` `+` `3/7` `=` `\frac{5 + 1 + 3}{7}` `=` `9/7`.

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`16/25` `+` `9/25` `=` `\frac{16 + 9}{25}` `=` `25/25` `=` `1`.

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`@Chy`

`@Thủy#Hoidap247`

`9/12 + 7/12 = (9+7)/12 = 16/12 = 4/3.`

`5/7 + 1/7 + 3/7 = (5+1+3)/7 = 9/7.`                 

`16/25 + 9/25 = (16+9)/25 = 25/25 = 1.`

Chúc bạn học tốt !!! ^^