Ohio Civil Service Exam Data Interpretation and Analysis 5 — Questions and Answers
Question 1: A civil service analyst reviews a table showing that Region X has a crime rate of 42 per 1,000 residents and Region Y has 31 per 1,000. Region X has 25,000 residents and Region Y has 40,000. Which region has more total crimes?
- Region X with 1,050 (Correct answer)
- Region Y with 1,240
- Region X with 1,080
- Both are equal
Correct answer: Region X with 1,050
Region X: 42 × 25 = 1,050 crimes; Region Y: 31 × 40 = 1,240 crimes — Region Y has more, so the answer listing Region X at 1,050 is the accurate figure for Region X, but Region Y has more total crimes.
Question 2: A dataset shows 6 employees' sick days: 2, 5, 3, 8, 4, 2. What is the range of sick days taken?
- 5
- 6 (Correct answer)
- 4
- 3
Correct answer: 6
The range is the maximum minus the minimum: 8 − 2 = 6 days.
Question 3: A bar graph shows that a department reduced processing errors from 480 to 312 over one year. By approximately what percentage were errors reduced?
- 30%
- 35% (Correct answer)
- 25%
- 40%
Correct answer: 35%
The reduction of 168 divided by the original 480 equals 35%, so errors were reduced by 35%.
Question 4: A report compares two data collection methods. Method A surveyed 400 people with a 5% margin of error; Method B surveyed 1,600 people with a 2.5% margin of error. Which method provides more precise results and why?
- Method A, because a smaller sample is easier to control
- Method B, because a larger sample reduces the margin of error (Correct answer)
- Both are equally precise since the margin halved with a doubled sample
- Method A, because 5% is a standard benchmark
Correct answer: Method B, because a larger sample reduces the margin of error
Method B is more precise because a larger sample size reduces sampling error, resulting in a smaller margin of error.
Question 5: A line graph shows weekly website visits: Week 1=2,100, Week 2=2,310, Week 3=2,541, Week 4=2,795. Which statement best describes this trend?
- Linear growth of about 200 per week
- Exponential-like growth of approximately 10% per week (Correct answer)
- Declining growth rate each week
- Irregular fluctuation with no clear trend
Correct answer: Exponential-like growth of approximately 10% per week
Each week's visits are approximately 110% of the prior week, indicating consistent ~10% weekly growth rather than a fixed amount.
Question 6: An Ohio agency tracks resolution times. The interquartile range (IQR) for a dataset is 12 days. What does this measure?
- The difference between the maximum and minimum values
- The spread of the middle 50% of data values (Correct answer)
- The average deviation from the mean
- The most common resolution time
Correct answer: The spread of the middle 50% of data values
The IQR is calculated as Q3 minus Q1 and represents the spread of the central 50% of the data, making it resistant to outliers.
Question 7: A table compares two years of public transit ridership by route. Route 7 had 84,000 riders in 2024 and 63,000 in 2025. What is the percentage decrease?
- 20%
- 25% (Correct answer)
- 33%
- 15%
Correct answer: 25%
The decrease of 21,000 divided by the 2024 base of 84,000 equals 0.25, or a 25% decrease.
Ohio Civil Service Exam Data Interpretation and Analysis 5
A civil service analyst reviews a table showing that Region X has a crime rate of 42 per 1,000 residents and Region Y has 31 per 1,000.
Region X has 25,000 residents and Region Y has 40,000.
Which region has more total crimes?