Grade 7 Mathematics Investigation – 7MD1 Investigation
Which pen should Ali build?
Student name:
Time allowed:
Class:
1 - 2 periods
Students work:
Individually
Ali has 35 camels.
He wants to build a new camel pen to look
after all of his camels.
The camel pen must follow these 3 rules:
Rule 1:
7 m2 of land per camel
1. How much area does Ali need on his camel pen?
m2
Some of the camel pen will be covered
with a roof and some will be uncovered.
Rule 2:
Ali wants the covered area to
be between 40 m2 and 70 m2
Rule 3:
Ali has 0.13 km of fencing.
This must go around the pen
two times.
2. Write 0.13 km in meters.
0.13 km = ___________ m
b) Explain how you found the answer:
7MD1.1
N E D
S2 Describe
3. Ali has 3 designs given to him.
Ali wants to choose the best one that fits rules 1 – 3.
a) Find the perimeter of Plan A:
Show how you estimate the perimeter.
Plan A
10 m
Covered Area
6m
6m
Uncovered Area
7MD1.3
15 m
N D
b) Will Ali have enough fencing to
surround the pen two times?
Explain your answer.
7MD1.3 N M
S2 Reason
c) Find the covered area of Plan A:
d) Using the diagram, explain why the area of the parallelogram is
base height
S2 Description 7MD1.4
N E D
e) Find the total area of Plan A:
7MD1.5
N
D
4. Plan B
The bottom 12 m by 9 m
section is uncovered.
a) Find the perimeter of Plan B:
Show how you estimate the
perimeter.
7MD1.3
N E D
b) Will Ali have enough fencing to
surround the pen two times?
Explain your answer.
7MD1.3 N M
S2 Reason
c) Find the covered area of Plan B:
d) Find the total area of Plan B:
7MD1.5
N E D
5. Plan C
a) Find the perimeter of Plan C:
This plan has exactly half uncovered
and half covered.
4m
5m
3m
4m
7MD1.3 N E
b) Will Ali have enough fencing to
surround the pen two times?
Explain your answer.
10 m
7MD1.3 N M
c)
S2 Reason
Find the total area of Plan C:
7MD1.5 N E D
d) Find the covered area of Plan C:
7MD1.5 N M
6. a) Ali sees an advertisement for
roofing:
25 cm2
a) How much is 500 cm2 in m2?
Explain how you got your answer.
5 cm
5 cm
7MD1.2
N
E
M
S2 Describe
b) Use this drawing to show that 4 tiles will cover 1 m2?
1 m = 100 cm
1m
c) How many tiles will Ali need for each of the Plans?
What will this cost?
Covered Area
[ 4 tiles cover 1 m2]
Number of tiles
Cost
Plan A
Plan B
Plan C
7MD1.4
N M
7MD1.5
N M
7. Make a table comparing the information that you know about each plan.
Covered Area
Total Area
Perimeter
Cost of Cover
Plan A
Plan B
Plan C
S1 Organizing Information/Data
b) Which plan should Ali choose?
Use the information from your table above to give reasons for your answer.
S3
Making a Decision