SOLUTION
Given the question in the question tab, the following are the solution steps to get the monthly bill for using one of their phones for 60 minutes in a month.
Step 1: Write the equation that gives the amount of money to be paid for t minutes a month

Step 2: Calculate the monthly bill for using one of their phones for 60 minutes a month

Hence, the monthly bill for using one of their phones for 60 minutes in a month is $41