High School Mathematics Problems from Alaska
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Sheet
for the Units and SelfAssessment
for Cultural Standards in Practice.
Predicting Plant Coverage
Beth Sukraw
MS
Word Download
Standards: Estimation
and Computation, Statistics and Probability
Performance Standards: A3.3.1,
A3.3.2, A3.3.3, A3.3.4, A3.3.5, A3.3.6, A3.4.1, A3.4.5, A3.4.6, A6.3.1, A6.4.1
Concepts: Estimating,
Organizing Data, Predicting, Computing in Percents, Decimals, and Setting up
and Solving proportions.
Carnegie Chapter: Analyzing
Data and Making Predictions, Connecting Situations to Equations.
Overview: During
the summer, our local biologists are out in the field studying plants using
a similar one meter by one meter square plot sample. If possible, call your
local botanist and go out into the field or have him/her bring in past records
and tools used to record plant coverage in your area. This is a great unit to
include local native language for plants. The estimation skills of the guest
speakers you bring to class should be emphasized.
Let’s explore a plant prediction
situation. In one square kilometer you randomly picked one square meter to
record as an example of the surrounding vegetation. You and your research
team did
this for several sites. You will use this chart to make predictions and answer
questions. For each problem, show all your work and write your answers in
complete
sentences.
The following is the square
metric chart you recorded. You constructed a key to show the vegetation. If
the square has the letter mentioned, it is over 50% of that plant in that 10
cm by 10 cm square.
Key:
S

Sedge

M

Moss

C

Cranberry

L

Lichen

O

Other

M

M

M

L

L

L

L

L

L

L

M

M

L

L

L

M

L

L

L

L

M

L

L

L

L

M

L

L

L

M

M

L

M

C

M

O

S

L

L

M

M

M

M

C

C

L

L

L

M

M

M

M

M

M

M

M

O

C

C

C

M

M

M

C

S

M

M

M

M

M

M

M

M

C

C

L

L

L

L

L

M

M

M

M

M

M

L

L

L

L

C

C

M

M

M

L

L

L

M

M

 Make a first prediction of
the percentage of each type of plant in the square meter. Use no computations.
At a glance, what percentage of each type of plant do you see?
____% Sedge
____% Moss
____% Cranberry
____% Lichen
____% Other
 Find the actual recorded
percentages for each type of plant in the square meter.
Plant Type

Tally

Frequency

Percentage Actual

Percentage Estimate from
question #1

Difference
Estimate Actual

Sedge






Moss






Cranberry






Lichen






Other






 Suppose the square meter
is a good sampling of the square kilometer it came from. Find how much of
the area in the square is covered by each type of plant.
Example: If 10% of the square
meter is covered by sedges, then
.10


x



=



1 m^{2}


1 km^{2}

x = 10,000
m^{2 }or .01 km^{2}

Keep
in mind that,

1
km

=

1,000
m

Plant Type

Coverage
Area in Square km

Sedge


Moss


Cranberry


Lichen


Other


 What is the total area (cm^{2})
covered by cranberries in
 1,000 square centimeters?
 2,000 square centimeters?
 100 square centimeters?
 Write an equation describing
the total area covered by cranberries.
 Construct a graph for the
cranberry coverage area. Label the axes and indicate the scale.
 What if the square meter
randomly picked as an example of the surrounding vegetation was a poor example?
Explain possible errors and implications.
 How could a sampling area
be picked to better exemplify the surrounding area other than randomly?
 The following table shows
the percentage results of 10 more onemeter square samples. Use this data
to estimate the overall area covered by each plant in the square kilometer.
Round to the nearest tenth of a percent.

C

S

M

L

O

1

22%

7%

31%

34%

6%

2

21%

1%

36%

38%

4%

3

21%

3%

21%

46%

9%

4

28%

14%

31%

24%

3%

5

20%

11%

48%

9%

12%

6

14%

15%

35%

29%

7%

7

5%

4%

53%

33%

5%

8

19%

9%

41%

25%

6%

9

28%

9%

39%

13%

11%

10

17%

6%

46%

29%

2%

____% Sedge
____% Moss
____% Cranberry
____% Lichen
____% Other
 Explain any changes that
occurred from your group’s estimate to the combined averages.
 Create a bar graph to illustrate
the estimated area covered by each plant in the square kilometer. Label your
axes, create an appropriate scale and give a title to your graph.
Table of
Contents
For the Teacher's Guides, please email Alaska
Native Knowledge Network
Handbook
for Culturally Responsive Science Curriculum by Sidney Stephens
Excerpt: "The information and insights contained in this document will be
of interest to anyone involved in bringing local knowledge to bear in school
curriculum. Drawing upon the efforts of many people over a period of several
years, Sidney Stephens has managed to distill and synthesize the critical ingredients
for making the teaching of science relevant and meaningful in culturally adaptable
ways." 