Giúp mình với nhé m n cảm ơn các bạn

`A = 3/5 + 1/2`

`A = 6/10 + 5/10`

`A = 11/10`

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`B = 3/5 + 1/3 `

`B = 9/15 + 5/15`

`B = 14/15`

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`C = 23/15 + 4/15`

`C = 9/5`

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`D = 11/15 + 4/5`

`D = 11/15 + 12/15`

`D = 23/15`