How do a graph this?

Catherine needs to sell boxes of cookies as a fundraiser for a team. She starts with 135 boxes and begins selling at a constant rate of 15 boxes each day.



Use the Segment tool to plot a graph representing the number of boxes of cookies Catherine has left to sell from the time she begins selling until the cookies are gone.

So time the graph is like... at the bottom is Time (days) and the numbers are from 1 2 3 4 5 6 7 8 9 10 and 11. On the left side on the graph is Boxes left to sell and the numbers are 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150.

1 answer

To graph the scenario where Catherine sells boxes of cookies, follow these steps:

  1. Understand the Data:

    • Starting number of boxes: 135
    • Selling rate: 15 boxes per day
    • Time period until cookies are sold out: \( \frac{135}{15} = 9 \) days. She will have 0 boxes left after 9 days.
  2. Create a Table of Values:

    • You can create a table that shows how many boxes are left at the end of each day.

    | Days (x) | Boxes Left (y) | |----------|-----------------| | 0 | 135 | | 1 | 120 | | 2 | 105 | | 3 | 90 | | 4 | 75 | | 5 | 60 | | 6 | 45 | | 7 | 30 | | 8 | 15 | | 9 | 0 | | 10 | 0 | | 11 | 0 |

  3. Set Up the Graph:

    • X-axis (Time in Days): This axis will represent the days (from 0 to 11).
    • Y-axis (Boxes Left to Sell): This axis will represent how many boxes are left (from 0 to 135, or up to 150 for the scale).
  4. Plot the Points:

    • Plot each point from the table on the graph:
      • (0, 135)
      • (1, 120)
      • (2, 105)
      • (3, 90)
      • (4, 75)
      • (5, 60)
      • (6, 45)
      • (7, 30)
      • (8, 15)
      • (9, 0)
      • (10, 0)
      • (11, 0)
  5. Draw Segments:

    • Connect the points with straight lines. The graph will begin at (0, 135) and have a downward slope until (9, 0). After day 9, the line will remain flat along the horizontal line at 0 boxes sold for days 10 and 11.
  6. Label Your Graph:

    • You can label the axes ("Days" for the x-axis and "Boxes Left to Sell" for the y-axis), and also give the graph a title like "Catherine's Cookie Sales."
  7. Analyze the Graph:

    • You will observe that the graph is linear (straight line) until the 9th day, demonstrating a steady decrease in the number of boxes sold at a rate of 15 per day, followed by a flat line indicating no more boxes left after day 9.

Once you have completed these steps, you will have successfully graphed the number of boxes Catherine has left to sell over time!