summative test 1 q4

Which of the following best defines the first quartile (Q1)?

• The middle value of the dataset

• The highest value in the dataset

• The median of the lower half of the dataset

• The median of the upper half of the dataset

How many quartiles are there in a dataset?

• 2

• 3

• 4

• 5

If a dataset has 20 values, what position corresponds to the third quartile (Q3)?

• 5th value

• 10th value

• 15th value

• 20th value

Which of the following measures tells us how far apart the first quartile (Q1) and the third quartile (Q3) are?

• Variance

• Standard deviation

• Interquartile range (IQR)

• Mean absolute deviation

A dataset consists of the numbers: 8, 12, 15, 18, 20, 22, 25, 28, 30. What is the first quartile (Q1)?

• 13.5

• 15

• 18

• 20

If the interquartile range (IQR) of a dataset is 12 and the first quartile (Q1) is 18, what is the third quartile (Q3)?

• 24

• 30

• 36

• 40

A company records the monthly salaries of 10 employees in thousands: 25, 28, 30, 32, 34, 36, 38, 40, 42, 45. What is the median salary?

• 30

• 34

• 35

• 40

A student scored at the third quartile (Q3) in a math test. What conclusion can be made about the student's performance?

• The student’s score is the highest in the class.

• The student’s score is equal to the class median.

• The student performed worse than 75% of the class.

• The student performed better than 75% of the class.

A group of students recorded their daily study hours, and the first quartile (Q1) was 1 hour while the third quartile (Q3) was 3 hours. One student claims that most of them study around 2 hours a day. Is this claim reasonable?

• Yes, because 2 hours is the lowest study time recorded.

• No, because Q3 shows that most students study for over 3 hours.

• No, because Q1 shows that most students study for less than 1 hour.

• Yes, because 2 hours is between Q1 and Q3, representing the middle 50% of study times.

A school principal analyzed students’ exam scores and found that a student scored below Q1. What can the principal infer about this student’s performance?

• The student is in the lowest 25% of the class.

• The student’s score is exactly at the median.

• The student is among the top performers in the class.

• The student scored within the middle 50% of the class.