A cell phone carrier charges a fixed monthly fee plus a constant rate for each minute used. Part 1. In January, the total cost for 175 minutes was \( \$ 48.5 \) while in February, the total cost for 325 minutes was \( \$ 51.5 \). The constant charge for each minute used is: 0.04 0.03 0.02

To find the constant charge per minute, we can set up a system of equations based on the information given: Let \( F \) be the fixed monthly fee and \( r \) be the rate charged per minute. From January's data (175 minutes): \[ F + 175r = 48.5 \quad (1) \] From February's data (325 minutes): \[ F + 325r = 51.5 \quad (2) \] Now, we can solve these equations. First, let's subtract equation (1) from equation (2): \[ (F + 325r) - (F + 175r) = 51.5 - 48.5 \] \[ 150r = 3 \quad \Rightarrow \quad r = \frac{3}{150} = 0.02 \] The constant charge for each minute used is \( 0.02 \) dollars. --- It's interesting to note that mobile phone plans have evolved over the years. Initially, providers charged by the minute, which meant long conversations could lead to hefty bills. As demand for mobile communication soared, and the introduction of unlimited plans became common, the industry witnessed dramatic pricing shifts, making it easier for users to communicate without worrying about minutes! In a nutshell, understanding your plan can save you quite a bit! It’s crucial to calculate how many minutes you typically use and compare it with available plans. Sometimes opting for a higher fixed fee can lead to savings if you regularly exceed the minute threshold of cheaper plans. Smart planning can transform your mobile expenses from a headache into a budget boost!