Question

What has to be added to the sum of 5/7 and 7/5 to get 3? Give the awnser as either a whole number or fraction- no decimal awnsers

Answer 1

Let

x ----> the number

we have that

`(5)/(7)+(7)/(5)+x=3`

Solve for x

`x=3-((5)/(7)+(7)/(5))`
`\begin{gathered} x=3-((5*5+7*7)/(35)) \\ x=3-((74)/(35)) \end{gathered}`
`\begin{gathered} x=((35*3-74)/(35)) \\ \\ x=(31)/(35) \end{gathered}`

therefore

The number is 31/35