Sketch your examples, labeling both axes Z Learning Objective To be able to construct linear graphs arising from real life problems To be able to discuss and interpret graphs modeling real situations Cell Phone Data? Working in your teams discuss what data about mobile phones could be represented on a straight line graph You need to identify two specific examples Sketch your examples, labeling both axes

Pay as you Go Cell Phones: Independent Work Z Pay as you Go Cell Phones: Independent Work Working independently, work through the instructions on the sheet When instructed, discuss your answer for step 4 with your team Help your team mates to complete their sheets

Pay as you Go Cell Phones: Team Work Z Pay as you Go Cell Phones: Team Work Discuss the questions on the sheet in your teams Ensure you all complete your own sheet with your agreed answers Create your own question based on the data provided

Pay as you Go Cell Phones 1 Straight Line Graphs Pay as you Go Cell Phones 1 Name: Step 1: Complete the four tables on sheet 2 for the following Pay as you Go Cell Phone deals: Phone is $50 Calls 35cents per min Phone is $45 Calls 40cents per min Phone is $60 Calls 30cents per min Phone is $80 Calls 10cents per min Step 2: Using the values in your tables, plot each of the Cell Phone deals on the graph on sheet 2, take care to ensure you plot the points and draw the lines accurately (use a different colored pencil for each line). Ensure your lines and axes are labeled correctly. Step 3: Write down the equation of the line (in the form y = mx + c) for each of the Cell phone deals: O2: Virgin: T-mobile: 3: Step 4: Explain below why it is important to identify the number of calls you are likely to make before selecting a Pay as you Go Cell phone deal. Use examples to illustrate your point.

Pay as you Go Mobile Phones 3 Straight Line Graphs Pay as you Go Mobile Phones 3 Name: Discuss the answers to the following questions in your team, then write down your own answers. 1. How many minutes of calls do you need to make for the 3 phone to be the cheapest deal? 2. Jane estimates that she will make 7 minutes of calls per month over a year. a. Based on your graph, what phone deal would you recommend she purchases? b. How much will this cost her? c. If she chose an alternative provider, what is the most it could cost her? Who is this with? d. Calculate your answers to b and c using the relevant equations: 3. Hiresh needs a phone for 6 months and he estimates that he will make between 90 and 130 minutes of calls in that time. What phone deal would you recommend he purchases and why? Provide examples of call costs in your answer. 4. Grandpa Bob wants to buy his first mobile phone, he has $200 in total to spend on the phone and calls over 2 years. What is the maximum number of calls he can make? Which provider is this with? Show your working.

Calls (min) 50 100 200 250 Cost ($) Calls (min) 50 100 200 250 Cost ($) 2 Z Calls (min) 50 100 200 250 Cost ($) Calls (min) 50 100 200 250 Cost ($) 150 100 50 50 100 150 200 250

Cost ($) No. of Minutes 2 150 100 50 50 100 150 200 250 Z Calls (min) 50 100 200 250 Cost ($) 67.5 85 120 137.5 Calls (min) 50 100 200 250 Cost ($) 45 65 85 125 145 2 Calls (min) 50 100 200 250 Cost ($) 60 75 90 120 135 Calls (min) 50 100 200 250 Cost ($) 80 85 90 105 150 Virgin O2 T-mobile 3 100 Cost ($) 50 50 100 150 200 250 No. of Minutes