Quiz Week 9

If the scores of five students are 98, 92, 89, 84, and 81, what is the average (mean) of their grades?

• 88.8

• 89.5

• 87.5

• 90.2

In a class, the final grade is determined by homework (30%), quizzes (20%), and the final exam (50%). A student scored 80 on homework, 75 on quizzes, and 90 on the final exam. What is the student's final weighted grade?

• 82.5

• 85.0

• 86.5

• 84.0

A company uses weighted averages to calculate employee performance scores. The employee's performance is evaluated based on Communication (30%), Productivity (40%), and Teamwork (30%). An employee received scores of 90 in Communication, 85 in Productivity, and 88 in Teamwork. What is the employee’s final performance score?

• 87.7

• 88.5

• 89.2

• 87.4

A survey of 250 households is conducted in a town. Based on the survey, the following results are found. What is the average number of pets per household?

• 1.32

• 1.45

• 1.67

• 1.80

A survey of 300 households is conducted to determine how many TVs each household has. The following results are recorded. What is the average number of TVs per household?

• 1.57

• 1.66

• 1.78

• 1.90

• 0.644

• 0.522

• 0.467

• 0385

• 104.3

• 105.6

• 106.7

• 109.1

• 0.661

• 0.653

• 0.645

• 0.513

Which of the following best defines Simpson's Paradox?

• A situation where increasing sample size causes results to become less accurate.

• A phenomenon where a trend appears in different groups of data but disappears or reverses when the groups are combined.

• A paradox in which small changes in one variable lead to unexpectedly large changes in another.

• A mathematical error that occurs when averages of percentages are incorrectly calculated.

Which of the following best defines an Index?

• A method for solving equations by manipulating variables.

• A statistical measure that represents and tracks changes in a specific variable or group of variables over time.

• A number that represents the most frequent value in a dataset.

• A graph used to show the relationship between two quantities.