What is the value of m?

6. \(\left\{ 4,\;3,\;7,\;1\right\}\)
If \(m\) is a number so that the sum of \(m\) and any number in the set above is also in the set, what is the value of \(m\)?

  1. -1
  2. -2
  3. 4
  4. 3
  5. 0

m must be zero, because when we add zero to any number in the set will give us another number in the set.


\begin{align} \bigl\{4, 3, 7, 1\bigl\} +0=\begin{cases}
      4+0=4\\
      3+0=3\\
      7+0=7\\
      1+0=1
    \end{cases}\end{align}


Answer: (E)