A teacher has asked all the students in the class which days of the week they read after 9 pm. which of the following is the best way to display the percent of number of students for each day of the week?
A.
Histogram
B.
Pie graph
C.
Scatter plot
D.
Bar graph
The correct answer and explanation is:
The correct answer is:
D. Bar graph
Explanation:
When visualizing the percentage of students who read after 9 PM on different days of the week, a bar graph is the best choice. A bar graph is ideal for displaying categorical data, where each category (in this case, the days of the week) is distinct and does not have a numerical order or relationship with other categories. Here’s why a bar graph is the most appropriate option:
- Clear Comparison: Bar graphs allow for easy comparison between different categories. Each day of the week can be represented as a separate bar, and the height of the bar corresponds to the percentage of students who read on that particular day. This makes it simple to see which days have more or fewer students reading after 9 PM.
- Categorical Data Representation: Days of the week are categorical data—they represent different categories without a natural numerical order. A bar graph is specifically designed for such data, where each bar stands for a separate category, and the length or height of the bar indicates the value associated with that category.
- Visual Clarity: Bar graphs provide a clear visual representation, making it easy to see trends or patterns. For instance, if most students read on weekends, the bars for Saturday and Sunday will be taller, immediately highlighting this trend.
Why Not the Other Options?
- Histogram: Histograms are used for continuous data divided into intervals (bins). They are not suitable for categorical data like days of the week.
- Pie Graph: Pie charts are useful for showing proportions as parts of a whole but are less effective when comparing multiple categories side by side. They are also harder to read when there are many categories (like seven days).
- Scatter Plot: Scatter plots show relationships between two numerical variables and are not designed for categorical data.
Thus, a bar graph is the most effective tool to display the percentage of students reading after 9 PM for each day of the week.