WASHINGTON STATE MATHEMATICS COUNCIL

2001 MIDDLE SCHOOL MATH OLYMPIAD

 
Session I  ~  Problem Solving

Phone Trees

5-8

 

Rubric/Scoring Guidelines

 

The score for each team for Session I is the average of the 5 scores below (maximum 4 points).

 

Points

CORRECT ANSWER

4

·          Accurately shows and explains  the following times ending within a round (i.e., clearly showing that the last full round is not needed): 

Plan                           10,000 Households                         50,000 Households

3-Call Plan      justified time within 24-27 minute range     justified time within 27-30 minute range

5-Call Plan      justified time within 25-30 minute range      justified time within 30-35 minute range 10:53

®  7/8 only:  Shows correct times within rounds for a third phone tree plan.

·         Shows that a complete round of calls does not have to be made to complete the phone calls In all cases.

·         Indicates that neither 10,000 nor 50,000 households can be reached in 15 minutes under either plan.

3

·         Accurately shows the following times (ending time end of round):

Plan                                10,000 Households                            50,000 Households

3-Call Plan                   27 min.    done by 10:48                     30 min.    done by    10:51

5-Call Plan                   30 min.    done by 10:51                     35 min.    done by    10:56

®  7/8 only:  Shows correct times for a third phone tree plan.

·         One or two calculation or reasoning errors in Rubric level 4 time answers/reasoning.

·         May not recognize that whole rounds are needed for the last round.

·         Indicates that neither 10,000 nor 50,000 households can be reached in 15 minutes under either plan.

2

·         One or two calculation errors in Rubric level 3 times shown above.

·         Does or may not recognize that whole rounds are needed for the last round.

·         May have data but does not reach (or state) decision regarding 15 minute goal.

0

·         Answer other than one of the above.

 

Points

PROBLEM UNDERSTANDING    Understand the problem – patterns, concepts, and approach

4

·         Correctly understands all required responsibilities.

·         Uses all necessary information and data.

3

·         Understands how to develop table or diagram, but does not use this for recommendation.

·         Uses necessary information and data.

2

·         Understands that the time required to alert households is of central importance.

·         May have neglected to use necessary information.

1

·         The task is incorrectly understood.

·         Information is incorrectly used or inaccurate.

0

·         No attempt at a response.

 

Points

STRATEGY      Choose and apply a valid strategy for each part of the problem solution.

4

·         Chose a valid strategy to develop tables/diagrams, summary, and recommendations.

·         Applied the strategy correctly, consistently, and completely.

3

·         Chose a valid strategy to develop tables/diagrams and make recommendations.

·         Applied the strategy correctly, but some breakdown in reasoning or logic. 

2

·         Strategy  was only partly fit for the task.

·         Strategy was partially or incorrectly completed.

1

·         Strategy did not apply to the task.

0

·         No attempted strategy.

 

 

Points

COMMUNICATION     

Explain all requested components of the final solution, using tables, symbols, labels, and correct vocabulary.

4

Using appropriate methods (tables, diagrams, terminology, symbols):

·         Communicated table/diagram, summary, and recommendations clearly.

·         Communicated strategy clearly and completely for table/diagram, summary, and recommendations.

·         Grammatical construction is basically correct.

3

Using appropriate methods (tables, diagrams, terminology, symbols):

·         Communicated table/diagram, summary, and recommendations clearly, BUT may have omitted reasoning connections, requiring the reader to make inferences.

·         Communicated strategy clearly and completely for table/diagram, summary, and recommendations, BUT may have omitted reasoning connections, requiring the reader to make inferences.

·         May include awkward grammar.

2

·         Communicated table/diagram, summary, recommendations, and strategy, but reasoning connections may be missing and inferences cannot be made.

·         Labels may be missing or directions may not have been completely followed.

1

·         Table/diagram, summary, recommendations, and strategy are not explained according to directions.

0

·         No evidence of explanation.

 

 

 

 

Points

CHECK FOR REASONABLENESS Demonstrate that entire solution has been reasoned through.

4

·         Discussed strongly valid reasons for time findings and recommendations.

·         Demonstrated (or inferred) through above discussion that findings and recommendations were checked for reasonableness.

3

·         Discussed valid reasons for time findings and recommendations.

·         Demonstrated (or inferred) through above discussion that findings and recommendations were checked for reasonableness.

2

·         (Reasonableness/Reasoning level between 3 and 1.)

1

·         Reasons for time findings and recommendations were not supported by evidence.

·         Demonstration (or inference) of check for reasonableness of findings and recommendations is not clearly evident.

0

·         Reasons for time findings and recommendations were not provided.

·         No evidence of demonstration (or inference) of check for reasonableness of  findings and recommendations.


7/8 Additional Phone Tree Tables

2-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:23

2

2

2

2

10:23  ¾  10:25

4

4

6

3

10:25  ¾  10:27

6

8

14

4

10:27  ¾  10:29

8

16

30

5

10:29  ¾  10:31

10

32

62

6

10:31  ¾  10:33

12

64

126

7

10:33  ¾  10:35

14

128

254

8

10:35  ¾  10:37

16

256

510

9

10:37  ¾  10:39

18

512

1,022

10

10:39  ¾  10:41

20

1,024

2,046

11

10:41  ¾  10:43

22

2,048

4,094

12

10:43  ¾  10:45

24

4,096

8,190

13

10:45  ¾  10:47

26

8,192

16,382

14

10:47  ¾  10:49

28

16,384

32,766

15

10:37  ¾  10:39

30

32,768

65,534

 

 

4-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:25

4

4

4

2

10:25  ¾  10:29

8

16

20

3

10:29  ¾  10:33

12

64

84

4

10:33  ¾  10:37

16

256

340

5

10:37  ¾  10:41

20

1,024

1,364

6

10:41  ¾  10:45

24

4,096

5,460

7

10:45  ¾  10:49

28

16,384

21,844

8

10:49  ¾  10:53

32

65,536

87,380

 

 

6-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:27

6

6

6

2

10:27  ¾  10:33

12

36

42

3

10:33  ¾  10:39

18

216

258

4

10:39  ¾  10:45

24

1,296

1,554

5

10:45  ¾  10:51

30

7,776

9,330

6

10:51  ¾  10:57

36

46,656

55,986

 

 

7-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:28

7

7

7

2

10:28  ¾  10:35

14

49

56

3

10:35  ¾  10:42

21

343

399

4

10:42  ¾  10:49

28

2,401

2,800

5

10:49  ¾  10:56

35

16,807

19,607

6

10:56  ¾  11:03

42

117,649

137,256

 

 

8-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:29

8

8

8

2

10:29  ¾  10:37

16

64

72

3

10:37  ¾  10:45

24

512

584

4

10:45  ¾  10:53

32

4,096

4,680

5

10:53  ¾  11:01

40

32,768

37,448

6

11:01  ¾  11:09

48

262,144

299,592

 

 

9-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:30

9

9

9

2

10:30  ¾  10:39

18

81

90

3

10:39  ¾  10:48

27

729

819

4

10:48  ¾  10:57

36

6,561

7,380

5

10:57   ¾  11:06

45

59,049

66,429

 

 

10-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:31

10

10

10

2

10:31  ¾  10:41

20

100

110

3

10:41  ¾  10:51

30

1,000

1,110

4

10:51  ¾  11:01

40

10,000

11,110

5

11:01  ¾  11:11

50

100,000

111,110

 

 

12-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:33

12

12

12

2

10:33  ¾  10:45

24

144

156

3

10:45  ¾  10:57

36

1,728

1,884

4

10:57  ¾  11:09

48

20,736

22,620

5

11:09  ¾  11:21

60

248,832

271,452

 

 

15-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

1

10:21  ¾  10:36

15

15

15

2

10:36  ¾  10:51

30

225

240

3

10:51  ¾  11:06

45

3,375

3,615

4

11:06  ¾  11:21

60

50,625

54,240

 

1-Person Tree

 

Round

Number

Time of Round

Total Minutes at End of Round

Total # of Calls Made During Round

Cumulative # of Calls at End of Round

10,000

10:21  + 10,000 min.

10,000

1

10,000

50,000

10:21  + 10,000 min.

50,000

1

50,000