Question

Giúp em vs ặ

Answer 1

a: =>25-x=15

=>x=10

b: \(=\dfrac{51}{102}\cdot\dfrac{81}{54}\cdot\dfrac{2}{5}=\dfrac{1}{2}\cdot\dfrac{2}{5}\cdot\dfrac{3}{2}=\dfrac{3}{10}\)

Answer 2

`a) (25-x)/40 = 3/8`

`=> (25-x)/40=(3xx5)/(8xx5)`

`=> (25-x)/40 = 15/40`

`=> 25-x=15`

`=> x=25-15`

`=> x=10`

Vậy `x=10`

`b) (81xx51xx14)/(102xx34xx35)`

`= 51/102 xx81/54xx2/5=1/2xx2/5xx3/2`

`=(1xx2xx3)/(2xx5xx2) `

`= 6/20`

`= 3/10`