Your cell phone plan costs ​$39.99 per month plus ​$0.13 for each text message you send or receive. You have at most ​$43 to spend on your cell phone bill. What is the maximum number of text messages that you can send or receive next​ month?

The maximum number of text messages is

calculated by subtracting the monthly cost of the plan from the maximum amount you can spend on your cell phone bill and then dividing the remaining amount by the cost per text message.

Maximum number of text messages = (Maximum amount to spend - Monthly plan cost) / Cost per text message
= ($43 - $39.99) / $0.13
= $3.01 / $0.13
≈ 23.15

Therefore, the maximum number of text messages you can send or receive next month is approximately 23.