STAT Data Interpretation from Graphs 5 — Questions and Answers
Question 1: A bar chart shows annual sales for a retail store. Sales in 2022 were $500,000 and in 2023 were $425,000. What was the percentage decrease in sales?
- 15% (Correct answer)
- 17.6%
- 20%
- 12.5%
Correct answer: 15%
Percentage decrease = (500,000 − 425,000) / 500,000 × 100 = 75,000/500,000 × 100 = 15%.
Question 2: Two overlapping circles in a Venn diagram represent students who play Soccer (30 total) and Basketball (25 total) with 10 students in the overlap. How many students play at least one sport?
- 55
- 45 (Correct answer)
- 35
- 65
Correct answer: 45
Using the inclusion-exclusion principle: 30 + 25 − 10 = 45 students play at least one sport.
Question 3: A line graph shows an exponential growth curve for a bacteria population, doubling every hour. After 4 hours starting with 100 bacteria, what does the graph show as the final count?
- 400
- 800
- 1,600 (Correct answer)
- 3,200
Correct answer: 1,600
Doubling 4 times: 100 × 2⁴ = 100 × 16 = 1,600 bacteria.
Question 4: A scatter plot has a best-fit line with the equation y = 3x + 5, where x = study hours and y = score. What score does the model predict for a student who studies 8 hours?
- 24
- 29 (Correct answer)
- 32
- 19
Correct answer: 29
y = 3(8) + 5 = 24 + 5 = 29.
Question 5: A bar chart compares the populations of four cities. City W = 2.1M, City X = 3.4M, City Y = 1.8M, City Z = 2.9M. Approximately what fraction of the total population lives in City X?
- One-quarter
- One-third (Correct answer)
- One-half
- Two-fifths
Correct answer: One-third
Total = 10.2M; City X = 3.4M; 3.4/10.2 ≈ 0.333, which is approximately one-third.
Question 6: A pictograph uses car icons where each icon represents 500 cars sold. Brand A shows 6 icons, Brand B shows 4.5 icons. How many more cars did Brand A sell than Brand B?
- 500
- 750 (Correct answer)
- 1,000
- 1,250
Correct answer: 750
Brand A: 6 × 500 = 3,000; Brand B: 4.5 × 500 = 2,250; difference = 3,000 − 2,250 = 750.
Question 7: A graph shows three companies' profit margins over five years. Company 1 is consistently above the others, but its line is nearly flat while the others slope upward steeply. What is the best prediction for year 6?
- Company 1 will likely still have the highest margin
- Company 2 or 3 may overtake Company 1 if current trends continue (Correct answer)
- Company 1 will drop to zero margin
- All companies will converge to the same margin
Correct answer: Company 2 or 3 may overtake Company 1 if current trends continue
If the upward slopes of Companies 2 and 3 continue while Company 1 stays flat, one or both will eventually exceed Company 1's margin.
STAT Data Interpretation from Graphs 5
A bar chart shows annual sales for a retail store.
Sales in 2022 were $500,000 and in 2023 were $425,000.
What was the percentage decrease in sales?