Question

2.8 over 4 = 7 over x

Answer 1

Starting with the equation:

`(2.8)/(4)=(7)/(x)`

Multiply both sides by 4x:

`\begin{gathered} (2.8)/(4)\cdot4x=(7)/(x)\cdot4x \\ \Rightarrow(2.8\cdot4\cdot x)/(4)=(7\cdot4\cdot x)/(x) \\ \Rightarrow(4)/(4)\cdot2.8\cdot x=(x)/(x)\cdot7\cdot4 \\ \Rightarrow2.8\cdot x=7\cdot4 \end{gathered}`

Notice that after multiplying both sides by 4x, each expression was simplified as a fraction, since 4/4 = 1 and x/x=1 for every x different from 0.

Now, simplify the product 7 times 4:

`2.8x=28`

Divide both sides by 2.8: