State Test Practice Data Analysis & Statistics 2 — Questions and Answers
Question 1: If you flip a fair coin, what is the probability of getting heads?
- 1/4
- 1/3
- 1/2 (Correct answer)
- 2/3
Correct answer: 1/2
A fair coin has two equally likely outcomes (heads or tails), so the probability of heads is 1 out of 2, or 1/2.
Question 2: A bag contains 3 red marbles, 4 blue marbles, and 3 green marbles. What is the probability of randomly drawing a blue marble?
- 3/10
- 2/5 (Correct answer)
- 1/3
- 4/7
Correct answer: 2/5
There are 4 blue marbles out of 10 total, giving a probability of 4/10, which simplifies to 2/5.
Question 3: A stem-and-leaf plot shows: Stem 2 | Leaves: 3, 5, 8. What values does this represent?
- 2, 3, 5, 8
- 23, 25, 28 (Correct answer)
- 32, 52, 82
- 2.3, 2.5, 2.8
Correct answer: 23, 25, 28
In a stem-and-leaf plot, the stem represents the tens digit and each leaf represents the ones digit, so stem 2 with leaves 3, 5, 8 equals 23, 25, and 28.
Question 4: Which measure of central tendency is most affected by extreme outlier values?
- Mode
- Median
- Mean (Correct answer)
- Range
Correct answer: Mean
The mean uses all values in its calculation, so a very high or very low outlier can significantly pull the mean away from the center of the data.
Question 5: A survey of 20 students found that 12 prefer math and 8 prefer reading. What percentage prefer reading?
- 20%
- 30%
- 40% (Correct answer)
- 60%
Correct answer: 40%
To find the percentage, divide 8 by 20 and multiply by 100: (8 ÷ 20) × 100 = 40%.
Question 6: In a frequency table, what does the frequency column tell you?
- The percentage of each category
- The number of times each value occurs (Correct answer)
- The range of the data set
- The cumulative running total
Correct answer: The number of times each value occurs
The frequency column records how many times each value or category appears in the data set.
Question 7: A scatter plot shows points generally trending from the lower-left to the upper-right. What does this indicate?
- No correlation between the variables
- A negative correlation between the variables
- A positive correlation between the variables (Correct answer)
- A random distribution of data
Correct answer: A positive correlation between the variables
When both variables increase together and points trend from lower-left to upper-right, this indicates a positive correlation.
State Test Practice Data Analysis & Statistics 2
If you flip a fair coin, what is the probability of getting heads?