Finding a Horizontal Stretch for a Tabular Function

A function $f\left(x\right)$ is given as the table. Create a table for the function $g\left(x\right)=f\left(\frac{1}{2}x\right).$

$$\begin{array}{ccccc}x& \text{2}& \text{4}& \text{6}& \text{8}\\ f\left(x\right)& \text{1}& \text{3}& \text{7}& \text{11}\end{array}$$

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Algebra and Trigonometry 2e · §3.5 Transformation of Functions · Example 11