Life Saver, anyone? |
Lifeguard
Applications of Mathematics 9 |
Lesson Idea by: Leanne Zorn, Mount Boucherie Secondary School,
Central Okanagan School District
Lifeguards work hard to keep swimmers at beaches and pools safe. The job involves cautioning people, administering first aid when required, maintaining a safe swimming environment, and when necessary, rescuing someone.
"A lot of what lifeguards do is public relations," notes Glenn Schulz, lifeguard supervisor for beaches and pools in Vancouver. Lifeguards need to be outgoing, good at motivating people, and sensitive to the needs of others. Basic requirements for all lifeguards are good health, physical fitness and the ability to swim well. The willingness to accept responsibility and the ability to exercise good judgement are also important qualities.
In order to keep their skills sharp, lifeguards often compete against each other in first aid competitions. "The officials running lifeguard competitions like to mix the events up a bit," says Schulz. "That way competitors have to have well-rounded skills." Sometimes there are also timed fitness competitions. Most often, it's in such competitions that lifeguards put their math skills to use. They might also use math to figure out the volume of water in a pool (although this is rare) or determine rankings in a swimming competition.
Get in groups of three to compete in a fitness test against your classmates. The events for this competition include:
Each member of your group will perform in one of the above competitions. For each event, there will be one competitor, one timer and one counter. The timer will tell the competitor when to begin and will warn the competitor when there are only 10 seconds left. The counter will count aloud the number of sit-ups, flights or push-ups done. Record the results on the Student Activity Sheet.
In this competition, the events are not equally weighted. In other words, some are worth more than others:
1. The sit-up competition is worth 30 per cent.
2. The stair competition is worth 50 per cent.
3. The push-up competition is worth 20 per cent.
Convert each event score into a percentage score, using your knowledge of proportions. These new scores will then be added together to determine your total team score out of 100.
Record your percentage scores and team score on the student activity chart.
Record your team score on the chalkboard, along with all the others in the class. How did you rank compared with the other teams in the class?
Change the weightings to give more emphasis to the sit-ups competition. Recalculate your score and compare your new ranking.
What would be the optimum weighting for your team?
In lifeguard competitions, teams or individuals compete against each other in a series of contests. The individual competitions are designed to test various skills, including:
CPR, in which a team of lifeguards is assessed on its ability to give cardiopulmonary resuscitation;
Priority action approach, in which a team is given 90 seconds to give initial treatment to a number of injured people;
Pool first aid, in which a team is given eight to 10 minutes to give treatment to several "injured" people in the pool;
Dry-land first aid, which is the same as pool first aid, except it is on dry land.
You're a member of a three-person lifeguard team that's competing in the annual Vancouver Ironguard Lifeguard Competition. This year's events include:
1. CPR skills worth 5 per cent;
2. Priority action approach worth 15 per cent;
3. Pool first aid worth 50 per cent;
4. Dry-land first aid worth 30 per cent;
Each event has its own score. Your team scored:
| CPR skills contest: |
135 |
| |
150 |
| |
| priority action approach: |
190 |
| |
200 |
| |
| pool first aid: |
225 |
| |
250 |
| |
| dry-land first aid: |
150 |
| |
200 |
You think your team did pretty well, but you'd really like to know how your team stacked up against the four other teams competing in this year's contest.
| The team from Prince George scored: |
85.75 |
| |
100 |
| |
| The team from Kelowna scored: |
81.50 |
| |
100 |
| |
| The team from Nanaimo scored: |
75 |
| |
100 |
| |
| The team from Victoria scored: |
83.65 |
| |
100 |
How did your team rank?
| Course/Grade: Applications of Mathematics 9 |
Curriculum Organizer:
Number Operations, Problem Solving |
Curriculum Sub-organizer(s):
Rational number operations
|
Prerequisites:
Ratio, Proportion and Per cent |
Resources:
· calculators
· stop watches
|
Student Activity Sheet - Life-Saver, Anyone?
|
Team Name:
_____________________________________________________________
1. Event: Sit-Ups Name:
______________________________________________________
Number achieved out of maximum 75: _________________________
Converted score out of 30: __________________________________
2. Event: Flights of Stairs Name: ______________________________________________________
Number achieved out of maximum 15: _________________________
Converted score out of 50: __________________________________
3. Event: Push-Ups Name: ______________________________________________________
Number achieved out of maximum 50: _________________________
Converted score out of 20: __________________________________
What was your team's total score out of 100? ______________
How did you rank compared with your classmates? ____________ |
|
Solution to Learn
First, you need to convert each event score into a percentage score by using your knowledge of proportions. Then, add up all percentage scores to determine your final score.
CPR skills component is worth five per cent.
135*5 = 150x
x = (135 *5)/150
x = 4.5
Therefore, your CPR score is 4.5 out of 5.
Priority action approach is worth 15 per cent.
190*15 = 200x
x = (190*15)/200
x = 14.25
Therefore, your priority action score is 14.25 out of 15.
Pool first aid is worth 50 per cent.
225*50 = 250x
x = (225*50)/250
x = 45
Therefore, your pool first aid score is 45 out of 50.
Dry-land first aid is worth 30 per cent.
30*150 = 200x
x = (30*150)/200
x = 22.5
Your dry-land first aid score is 22.5 out of 30.
To get your total score, add up these new scores for each event:
4.5 + 14.25 + 45 + 22.5 = 86.25
Since your total score is 86.25, your team is in first place! |
|
