Lesson 3

1. Lesson 3

1.8. Explore 3

Mathematics 30-3 Module 4

Module 4: Statistics

 

This is a photograph of a control valve inserted in a pipeline.

iStockphoto/Thinkstock

Weighted means can be used to solve problems that do not involve scores. Try to solve the following problem using weighted means. Can you think of another way to solve the problem?

 

Self-Check 2
  1. Control valves are used to regulate the flow of various fluids in industries. The company A1 Controls exports control valves to the United States, Russia, and Saudi Arabia. They ship 150 valves to the United States at $250/valve, 85 valves to Russia at $325/valve, and 210 valves to Saudi Arabia at $415/valve. What is the mean cost of shipping a valve to one of these three countries?  Answer
Did You Know?


The First Nations began playing lacrosse more than 500 years ago. Today the sport not only remains an integral part of native culture, but is played by thousands of people across Canada. From its origin as “The Creator's Game” to the popularity of the Toronto Rock team and the modern game, lacrosse has survived the test of time after treading down a long, controversial path that led it to become recognized as Canada's official national sport.

 

This is a photograph of a lacrosse racquet with a yellow ball in it.

Hemera/Thinkstock

 

Lacrosse teams may have up to 25 players. Ten of these players can be core players. Core players have more than three years of experience and make $500/game; first-year players make $200/game; second-year players make $250/game; and third-year players make $300/game.

  1. A lacrosse team has 8 core players, 5 first-year players, 9 second-year players, and 3 third-year players. Calculate the weighted mean for player payment per game. Answer
  2. Analyze the information provided in the table. Justify why one average salary is correct and the other is not.

    Department Salary Number of Employees
    Administration $55 000 50
    Marketing $65 000 100
    Engineering $75 000 4000
    Senior Management $120 000 15
    Top Management $1 200 000 5

    Average Salary (Wrong) $303 000
    Average Salary (Correct) $76 031

    Answer

 

textbook

  1. Answer “Build Your Skills” questions 3 to 8 from textbook pages 131 and 132. Answer


glossary
Add weighted mean to your copy of Glossary Terms.
Recall that mean is the sum of the values divided by the total number of values. In this specific case,  .