What is the value of m?

Name: What is the value of m?
Uploaded: 2011-02-08
Description: Solution 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)

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
-2
4
3
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)