An internet company changes its customers in the following way.
The internet is free for the first 10 hours each month and then it is charged at a rate of 12 cents per hour.
Derive a formula for calculating the cost $c of hours of internet use.
Answers
Answer:
Everyone needs data. But how do you get it and how much does it cost? Cable modem, cell phone data plan, voice minutes, text messages. Really, it isn't easy to compare these but fundamentally they are the same thing. In fact, I believe that eventually we will just pay one fee for data and it won't be split into these silly little types.
What I would like to get is a comparison of how much it costs to get your data for a mobile device. In this case, you can have three things: data (really they are all data), voice, and text messages. Typically, a service provider will charge you differently for these different thingsI would love to get how much each data mode costs per amount of data ($ per GB). Is this easy? No. Why? Because you aren't charged a rate like this. For instance. AT&T charges $25 for a 2 GB data plan. In this case, I could consider that the data costs $12.5 per GB. However, what if you don't use all 2 GB of data? What if you just use 700 MB during that month? Oh, what if you go over 2 GB? What then?
So, maybe you see the problem. Here is my solution. I will look at several providers. For each, I will take a typical user and estimate how much they use and how much they pay. Then I will make a maximum data use scenario. Don't worry, this might make sense after I do it.
Some Starting Estimates
How much data do you use? I am really going to just have to take some guesses here. Let me create a typical person (called Joe). This person has a smart phone with the following uses. (I am ignoring multimedia messages for now)
Talks on the phone for 500 minutes a month. I totally just made this number up. Just picking 8 kbps data rate (I know it is actually more complicated than that), this would be 0.0285 GB.
500 plain text messages a month. Let me pretend that that the average text message is 40 characters long. If I assume each character is 1 byte, then this would be 1.86 x 10-5 GB.
My fake average person uses 600 MB of data (web pages, email, songs and stuff). If use 1024 MB per GB, this is 0.586 GB.Now I need a power user. What is the maximum that you could use? Oh, let me call this person Zelda