~ Tus học tốt nè ~
`2` : `3/4` + `2/3` x `1/2` = `2/1` x `4/3` + `2/3` x `1/2`
= `(2x4)/(1x3)` + `(2x1)/(3x2)`
= `8/3` + `1/3`
= `9/3` = `3`
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`b` `)`
`3/5` - `1/4` : x = `25/100`
`1/4` : x = `3/5` - `25/100`
`1/4` : x = `7/20`
x = `1/4` : `7/20`
x = `5/7`
--------------------
x × `4/5` + x × `1/5` = 1`3/5`
x × `4/5` + x × `1/5` = `8/5`
x × ( `4/5` + `1/5` ) = `8/5`
x × `1` = `8/5`
x = `8/5` : `1`
x = `8/5`
