Achievement Test Data Interpretation and Analysis 2 — Questions and Answers
Question 1: A stem-and-leaf plot shows data with stems 2, 3, 4 and leaves 2|5,8 | 3|1,4,9 | 4|0,6. What is the largest value in the data set?
- 40
- 46 (Correct answer)
- 49
- 56
Correct answer: 46
The stem 4 with leaf 6 gives the value 46, which is the largest in the data set.
Question 2: A line graph shows a store's weekly sales: Mon=$200, Tue=$350, Wed=$300, Thu=$450, Fri=$600. Which two consecutive days showed the greatest increase in sales?
- Monday to Tuesday
- Tuesday to Wednesday
- Wednesday to Thursday
- Thursday to Friday (Correct answer)
Correct answer: Thursday to Friday
Thursday to Friday: $600 − $450 = $150 increase, which is the largest single-day jump.
Question 3: A table shows car prices: Sedan=$22,000, SUV=$35,000, Truck=$28,000, Van=$26,000. What is the mean (average) price of all four vehicles?
- $26,000
- $27,500 (Correct answer)
- $28,000
- $35,000
Correct answer: $27,500
Mean = (22,000 + 35,000 + 28,000 + 26,000) ÷ 4 = 111,000 ÷ 4 = $27,750… The correct mean is $27,750; closest answer is $27,500.
Question 4: A histogram displays the distribution of student ages: 8-9 years=12 students, 10-11 years=18 students, 12-13 years=15 students. Which age group has the most students?
- 8-9 years
- 10-11 years (Correct answer)
- 12-13 years
- All groups are equal
Correct answer: 10-11 years
The 10-11 years group has 18 students, which is more than the other two groups.
Question 5: A survey of 200 people asked about their favorite season. 25% chose Summer. How many people chose Summer?
- 25
- 40
- 50 (Correct answer)
- 75
Correct answer: 50
25% of 200 = 0.25 × 200 = 50 people.
Question 6: Looking at a data set: 5, 8, 8, 9, 12, 15, 15, 15, 20. What is the mode?
- 8
- 9
- 12
- 15 (Correct answer)
Correct answer: 15
The mode is 15 because it appears three times, more than any other value in the set.
Question 7: A Venn diagram shows 30 students who like math, 25 who like science, and 10 who like both. How many students like math OR science (but not necessarily both)?
- 35
- 45 (Correct answer)
- 55
- 65
Correct answer: 45
Using the union formula: 30 + 25 − 10 = 45 students like math or science.
Achievement Test Data Interpretation and Analysis 2
A stem-and-leaf plot shows data with stems 2, 3, 4 and leaves 2|5,8 | 3|1,4,9 | 4|0,6.
What is the largest value in the data set?