Giải :
`3/4 : x/6 = 0,76`
`→ 3/4 : x/6 = 19/25`
`→ x/6 = 3/4 : 19/25`
`→ x/6 = 75/76`
`→ 76 . x = 75 . 6`
`→ 76 . x = 450`
`→ x = 450/76 = 225/38`
Vậy `x = 225/38`
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` 2,5 . 45/x = 5/6`
`→ 45/x = 5/6 : 5/2`
`→ 45/x = 1/3`
`→ x = 45 . 3`
`→ x =135`
Vậy `x = 135`
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` 7,75 - ( 0,5 . x : 5 - 6,2 ) = 5 `
`→ 0,5 . x : 5 - 6,2 = 7,75 - 5`
`→ 0,5 . x : 5 = 2,75 + 6,2`
`→ 0,5 . x = 8,95 . 5`
`→ x = 44,75 : 0,5`
`→ x = 89,5`
Vậy `x = 89,5`
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$x . 150 - x . 75 = 300^{}$
`→ x . ( 150 - 75 ) = 300`
`→ x . 75 = 300`
`→ x = 300 : 75`
`→ x = 4`
Vậy `x = 4`
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XIN HAY NHẤT AK
