SOLUTION
We want to solve the question
A number decreased by the sum of the number and four.
Now we have been told let the number be x.
So we have
[tex]\begin{gathered} sum\text{ of the number and 4 is } \\ (x+4) \\ decreasing\text{ we have } \\ x-(x+4) \end{gathered}[/tex]solving that we have
[tex]\begin{gathered} x-(x-4) \\ x-x+4 \\ 0+4 \\ =4 \end{gathered}[/tex]simplifying, the answer is 4