Question

 x+x:5.7,5+x:2.9=315

Answer 1

\(x+\frac{x}{5}.7,5+\frac{x}{2}.9=315\)

<=>10x+15x+45x=3150

<=>70x=3150

<=>x=45

tích nha

Answer 2

x:x+x:5.7,5+x:2.9=315

x:(5.7,5+2.9)+1=315

x:55,5=315-1

x:55,5=314

x=314.55,5

x=17427

dấu . là nhân