The following graph shows the number of customers who purchased something from a store in September and October. What is misleading about the graph?
The bar graph is titled
A. The bars do not touch.
B. The intervals on the vertical axis between 200 and 207 are not even.
C. The graph exaggerates the difference in the number of customers between September and October.
D. The graph is not misleading.
C. The graph exaggerates the difference in the number of customers between September and October.
Note: Your teacher will grade your responses to questions 16–17 to ensure that you receive proper credit for your answers.
You are surveying students to find out their opinion of the quality of food served in the school cafeteria. You decide to poll only those students who buy hot lunch at the school cafeteria on a particular day. Is your sample random? Explain
No, the sample is not random. A random sample would involve selecting students from the entire population of the school, regardless of whether or not they purchase hot lunch at the cafeteria on a particular day. By only surveying students who buy hot lunch on a specific day, the sample is biased towards those who regularly purchase lunch from the cafeteria, and may not accurately represent the opinions of the entire student population.
The table shows the rainfall, in inches, in the month of July for the years 2006 through 2011.
Year
2006
2007
2008
2009
2010
2011
Rainfall
4.5
4.4
4.1
4.2
3.9
4.0
Alex used the data to make the graph below.
A line graph representing the data in the table is shown.A line graph is titled July Rainfall.
The horizontal axis is labeled Year and is equally spaced. The axis scale starts at 2006 increases by 1 until ending at 2011.
The vertical axis is labeled Rainfall in inches and is equally spaced. The axis scale starts at 3.6 and increases by 0.1 until ending at 4.6.
The data points represented in the tabled are connected by line segments from left to right.
a) In what way could the graph be misleading?
b) How could you redraw the graph so that it is less misleading?
a) One potential way the graph could be misleading is if the vertical axis is not clearly labeled or scaled, making it difficult to accurately interpret the differences between the rainfall amounts. Additionally, if the scale on the vertical axis is not consistent or evenly spaced, it could exaggerate or minimize differences between the data points.
b) To make the graph less misleading, the vertical axis should be clearly labeled with a title that includes units of measurement. The axis should also be evenly scaled with equally spaced intervals to accurately represent the differences between the data points. Additionally, it might be helpful to include horizontal gridlines to help the viewer accurately interpret the differences between the data points.
Researchers count 30 tagged zebras and 150 total zebras in an area of a game reserve. If researchers had previously tagged 80 total zebras at the game reserve, about how many total zebras live at the game reserve? Write a proportion to estimate the total population.
If 30 zebras are tagged and there are 150 zebras total, then the ratio of tagged zebras to total zebras is 30/150 or 1/5.
If 80 total zebras are tagged, we can set up a proportion to estimate the total population:
tagged zebras/total zebras = tagged zebras in sample/total zebras in sample
Simplifying and plugging in the known values:
1/5 = 80/x
Cross-multiplying:
x = 5 * 80
x = 400
Therefore, our estimate for the total population of zebras at the game reserve is about 400.