Perimeter of Irregular Shapes Worksheet

Perimeter of Irregular Shapes Worksheet
  • Page 1
 1.  
Estimate the area of the shaded region in the following figure.

a.
185 square units
b.
205 square units
c.
145 square units
d.
200 square units


Solution:

Number of squares that are filled = 37

Number of squares that are half filled = 8

Total number of squares filled = 37 + (8 × 1 / 2 ) = 41

Area of the figure = total number of squares filled × area of each square

= 41 × 5 = 205

So, the area of the figure is 205 square units.


Correct answer : (2)
 2.  
Estimate the area of the shaded region in the figure shown.

a.
134 square units
b.
120 square units
c.
140 square units
d.
130 square units


Solution:

Number of squares that are completely filled = 10

Number of squares that are half filled = 6

Total number of squares filled = 10 + (6 × 1 / 2 ) = 13

Area of the figure = Total number of squares filled × Area of each square

= 13 × 10 = 130

So, the area of the figure is 130 square units.


Correct answer : (4)
 3.  
Estimate the area of the shaded region in the figure, if each square is of 3 sq.cm.

a.
154 sq.cm.
b.
162 sq.cm.
c.
136 sq.cm.
d.
148 sq.cm.


Solution:

Number of squares that are filled = 48

Number of squares that are half filled = 12

Total number of squares filled = 48 + (12 × 1 / 2 ) = 54

Area of the figure = total number of squares filled × area of each square

= 54 × 3 = 162

So, the area of the figure is 162 sq.cm.


Correct answer : (2)
 4.  
Estimate the area of the shaded region of the figure, if each square measures 2 square inches.


a.
60 square inches
b.
50 square inches
c.
70 square inches
d.
40 square inches


Solution:

Number of squares that are filled = 20

Number of squares that are half filled = 10

Total number of squares filled = 20 + (10 × 1 / 2 ) = 25

Area of the figure = total number of squares filled × area of each square

= 25 × 2 = 50

So, the area of the figure is 50 square inches.


Correct answer : (2)
 5.  
Estimate the area of the shaded region of the following figure.

a.
100 sq. units
b.
28 sq. units
c.
112 sq. units
d.
120 sq. units


Solution:

Number of squares that are filled = 28

Area of the figure = total number of squares filled × area of each square

= 28 × 4 = 112

So, the area of the figure is 112 sq. units.


Correct answer : (3)
 6.  
Estimate the area of the figure if the area of each square is 4 mm2.

a.
9 mm2
b.
18 mm2
c.
13 mm2
d.
52 mm2


Solution:

Number of squares that are completely filled = 4

Number of squares that are almost filled = 4

Number of squares that are about half filled = 10

Number of squares covering the figure = 4 + 4 + (10 × 1 / 2 )

= 4 + 4 + 5 = 13
[Add.]

Area of the figure = Number of squares × Area of each square

= 13 × 4 mm2 = 52 mm2
[Multiply.]

So, the area of the figure is about 52 mm2.


Correct answer : (4)
 7.  
About how many square units does the figure occupy, if each square covers an area of 5 square units?

a.
80 square units
b.
22 square units
c.
16 square units
d.
8 square units


Solution:

Number of squares that are completely filled = 8

Number of squares that are almost filled = 2

Number of squares that are about half filled = 12

Number of squares occupied by the figure = 8 + 2 + (12 × 1 / 2 )

= 8 + 2 + 6 = 16
[Add.]

Number of square units occupied by the figure = Number of squares occupied by the figure × Area of each square

= 16 × 5 square units = 80
[Multiply.]

So, the figure occupies about 80 square units.


Correct answer : (1)
 8.  
Estimate the area covered by the figure, if the area of each square is 3 cm2.

a.
11 cm2
b.
36 cm2
c.
14 cm2
d.
42 cm2


Solution:

Number of squares that are completely filled = 4

Number of squares that are almost filled = 4

Number of squares that are about half filled = 8

Number of squares covered by the figure = 4 + 4 + (8 × 1 / 2 )

= 4 + 4 + 4 = 12
[Add.]

Area of the figure = Number of squares × Area of each square

= 12 × 3 cm2
[Multiply.]

So, the area covered by the figure is about 36 cm2.


Correct answer : (2)
 9.  
Each square in the figure covers an area of 2 in.2. What is the area of the figure shown?

a.
42 in.2
b.
48 in.2
c.
24 in.2
d.
20 in.2


Solution:

Number of squares that are completely filled = 8

Number of squares that are almost filled = 8

Number of squares that are about half filled = 10

Number of squares occupied by the figure = 8 + 8 + (10 × 1 / 2 )

= 8 + 8 + 5 = 21 in.2
[Add.]

Area of the figure = Number of squares covered by the figure × Area of each square

= 21 × 2 in.2 = 42 in.2
[Multiply.]

So, the area of the figure shown is about 42 in.2.


Correct answer : (1)
 10.  
Calculate the approximate area of the figure if the area of each square is 6 square units.


a.
270 square units
b.
45 square units
c.
260 square units
d.
288 square units


Solution:

Number of squares that are completely filled = 30

Number of squares that are almost filled = 12

Number of squares that are about half filled = 6

Number of squares occupied by the figure = 30 + 12 + (6 × 1 / 2 )

= 30 + 12 + 3 = 45
[Add.]

Area of the figure = Number of squares covered by the figure × Area of each square

= 45 × 6 square units = 270 square units
[Multiply.]

So, the area of the figure shown is about 270 square units.


Correct answer : (1)

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