The correct answer is 15 months. If you take the base fee of $50 than add $55 multiplied by 15 you will get $825 add the $50 it equals $875 for the second part your base fee is $200 multiply $45 by 15 which is the month and you get $675 add the $200 base fee and it is $875. The answer to your question is 15 months. Hope I helped
15 months; the amount will be $875. My work is shown in the attached pictures.