FAST Data Visualization and Interpretation 3 — Questions and Answers
Question 1: A stacked bar chart shows total monthly expenses divided into rent, food, and utilities. In March, the rent portion reaches $1,200 out of a $2,000 total bar. What percentage of March expenses went to rent?
- 50%
- 55%
- 60% (Correct answer)
- 65%
Correct answer: 60%
1,200 ÷ 2,000 = 0.60, so rent accounts for 60% of March's total expenses.
Question 2: Two overlapping circles in a Venn diagram show 30 elements in the left-only region, 20 in the overlap, and 15 in the right-only region. How many total unique elements are represented?
- 50
- 55
- 65 (Correct answer)
- 70
Correct answer: 65
Total unique elements = 30 (left only) + 20 (overlap) + 15 (right only) = 65.
Question 3: A line chart displays three years of quarterly revenue. Q3 consistently shows the highest values each year. This pattern is best described as what?
- A long-term upward trend
- A seasonal pattern (Correct answer)
- Random variation
- A structural break
Correct answer: A seasonal pattern
A recurring high point in the same quarter each year indicates a seasonal pattern — a predictable, repeating cycle tied to the time of year.
Question 4: On a pictograph, each symbol represents 50 items. A row shows 3.5 symbols. How many items does that row represent?
- 150
- 175 (Correct answer)
- 200
- 210
Correct answer: 175
3.5 symbols × 50 items per symbol = 175 items.
Question 5: A scatter plot's trend line (line of best fit) has a negative slope. A new data point falls far above the trend line. This point is best described as what?
- A data anchor
- An outlier (Correct answer)
- A cluster center
- A mode point
Correct answer: An outlier
A point that falls far from the line of best fit does not follow the general trend and is classified as an outlier.
Question 6: A frequency table lists test scores in ranges: 60–69 (4 students), 70–79 (11 students), 80–89 (9 students), 90–99 (6 students). What is the relative frequency of the 70–79 range?
- 36.7% (Correct answer)
- 36%
- 37%
- 34.5%
Correct answer: 36.7%
Total students = 30; relative frequency = 11/30 ≈ 0.367 = 36.7%.
Question 7: A bar chart has a broken y-axis that starts at 95 instead of 0, making a bar representing 99 appear four times taller than one representing 96. What is the primary risk of this presentation?
- It makes calculations easier
- It visually exaggerates differences between values (Correct answer)
- It removes outliers from view
- It compresses the data range
Correct answer: It visually exaggerates differences between values
A truncated y-axis amplifies visual differences, making small numerical differences appear much larger than they truly are.
FAST Data Visualization and Interpretation 3
A stacked bar chart shows total monthly expenses divided into rent, food, and utilities.
In March, the rent portion reaches $1,200 out of a $2,000 total bar.
What percentage of March expenses went to rent?