The cell phone plan cost $39.99 per month plus $0.17 for each text message you send or receive. The maximum amount you have to spend is $47.
let
the number of text message you send or receive = x
Therefore,
[tex]\begin{gathered} 39.99+0.17x\leq47 \\ 0.17x\leq47-39.99 \\ 0.17x\leq7.01 \\ x\leq\frac{7.01}{0.17} \\ x\leq41.2352941176 \end{gathered}[/tex]The maximum number of text message he can send or receive is approximately 41 .
