TCAP Data Analysis 2 — Questions and Answers
Question 1: A stem-and-leaf plot shows the following data: 3|2 5 8, 4|1 4 7 9, 5|0 3. What is the median of this data set?
- 41
- 44 (Correct answer)
- 45
- 47
Correct answer: 44
Listing all values in order: 32, 35, 38, 41, 44, 47, 49, 50, 53 — the middle (5th) value is 44.
Question 2: A survey asked 80 students to pick their favorite school subject. If 20% chose Math, how many students chose Math?
- 8
- 16 (Correct answer)
- 20
- 24
Correct answer: 16
20% of 80 = 0.20 × 80 = 16 students.
Question 3: Which measure of central tendency is most affected by an outlier in a data set?
- Mode
- Median
- Mean (Correct answer)
- Range
Correct answer: Mean
The mean uses all values in its calculation, so an extreme outlier shifts it significantly.
Question 4: A line graph shows a company's sales rising from $200 in January to $350 in June. What is the overall change in sales?
- $100
- $125
- $150 (Correct answer)
- $175
Correct answer: $150
$350 − $200 = $150 increase over the six-month period.
Question 5: In a frequency table, the category 'Blue' has a frequency of 15 out of 60 total responses. What is the relative frequency?
- 15%
- 20%
- 25% (Correct answer)
- 30%
Correct answer: 25%
15 ÷ 60 = 0.25, which equals 25%.
Question 6: A box plot has a minimum of 10, Q1 of 20, median of 30, Q3 of 45, and maximum of 60. What is the interquartile range (IQR)?
- 15
- 20
- 25 (Correct answer)
- 50
Correct answer: 25
IQR = Q3 − Q1 = 45 − 20 = 25.
Question 7: A scatter plot of hours studied vs. test scores shows points clustering from lower-left to upper-right. What type of correlation does this represent?
- Negative correlation
- No correlation
- Positive correlation (Correct answer)
- Perfect correlation
Correct answer: Positive correlation
Points trending from lower-left to upper-right indicate a positive correlation — as one variable increases, the other increases too.
TCAP Data Analysis 2
A stem-and-leaf plot shows the following data: 3|2 5 8, 4|1 4 7 9, 5|0 3.
What is the median of this data set?