Scroll:Measurement >> Area & Perimeter of Composite Figure >> ps (1743)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 36cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         36cm                 36cm

___cm2


Answer:_______________




2)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 12cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         12cm                 12cm

___cm2


Answer:_______________




3)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 16cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         16cm                 16cm

___cm2


Answer:_______________




4)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 26cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         26cm                 26cm

___cm2


Answer:_______________




5)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 24cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         24cm                 24cm

___cm2


Answer:_______________




6)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 14cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         14cm                 14cm

___cm2


Answer:_______________




7)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 18cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         18cm                 18cm

___cm2


Answer:_______________




8)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 10cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         10cm                 10cm

___cm2


Answer:_______________




9)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 32cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         32cm                 32cm

___cm2


Answer:_______________




10)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 28cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         28cm                 28cm

___cm2


Answer:_______________




 

1)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 36cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         36cm                 36cm

Answer: 833cm2


SOLUTION 1 :

           36cm                    36cm

 

Step 1: Diameter = 36cm

             Radius = 36 ÷ 2

                          = 18cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 18 x 18 ) - ( 12 x 18 x 18 )

                           = 92.502cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 92.502)

                                 → (π x 18 x 18) - (2 x 92.502)

                                  = 833.004cm2

                                  ≈ 833cm2



2)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 12cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         12cm                 12cm

Answer: 93cm2


SOLUTION 1 :

           12cm                    12cm

 

Step 1: Diameter = 12cm

             Radius = 12 ÷ 2

                          = 6cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 6 x 6 ) - ( 12 x 6 x 6 )

                           = 10.278cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 10.278)

                                 → (π x 6 x 6) - (2 x 10.278)

                                  = 92.556cm2

                                  ≈ 93cm2



3)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 16cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         16cm                 16cm

Answer: 165cm2


SOLUTION 1 :

           16cm                    16cm

 

Step 1: Diameter = 16cm

             Radius = 16 ÷ 2

                          = 8cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 8 x 8 ) - ( 12 x 8 x 8 )

                           = 18.272cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 18.272)

                                 → (π x 8 x 8) - (2 x 18.272)

                                  = 164.544cm2

                                  ≈ 165cm2



4)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 26cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         26cm                 26cm

Answer: 434cm2


SOLUTION 1 :

           26cm                    26cm

 

Step 1: Diameter = 26cm

             Radius = 26 ÷ 2

                          = 13cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 13 x 13 ) - ( 12 x 13 x 13 )

                           = 48.250cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 48.250)

                                 → (π x 13 x 13) - (2 x 48.250)

                                  = 434.498cm2

                                  ≈ 434cm2



5)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 24cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         24cm                 24cm

Answer: 370cm2


SOLUTION 1 :

           24cm                    24cm

 

Step 1: Diameter = 24cm

             Radius = 24 ÷ 2

                          = 12cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 12 x 12 ) - ( 12 x 12 x 12 )

                           = 41.112cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 41.112)

                                 → (π x 12 x 12) - (2 x 41.112)

                                  = 370.224cm2

                                  ≈ 370cm2



6)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 14cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         14cm                 14cm

Answer: 126cm2


SOLUTION 1 :

           14cm                    14cm

 

Step 1: Diameter = 14cm

             Radius = 14 ÷ 2

                          = 7cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 7 x 7 ) - ( 12 x 7 x 7 )

                           = 13.990cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 13.990)

                                 → (π x 7 x 7) - (2 x 13.990)

                                  = 125.978cm2

                                  ≈ 126cm2



7)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 18cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         18cm                 18cm

Answer: 208cm2


SOLUTION 1 :

           18cm                    18cm

 

Step 1: Diameter = 18cm

             Radius = 18 ÷ 2

                          = 9cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 9 x 9 ) - ( 12 x 9 x 9 )

                           = 23.126cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 23.126)

                                 → (π x 9 x 9) - (2 x 23.126)

                                  = 208.250cm2

                                  ≈ 208cm2



8)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 10cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         10cm                 10cm

Answer: 64cm2


SOLUTION 1 :

           10cm                    10cm

 

Step 1: Diameter = 10cm

             Radius = 10 ÷ 2

                          = 5cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 5 x 5 ) - ( 12 x 5 x 5 )

                           = 7.138cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 7.138)

                                 → (π x 5 x 5) - (2 x 7.138)

                                  = 64.274cm2

                                  ≈ 64cm2



9)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 32cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         32cm                 32cm

Answer: 658cm2


SOLUTION 1 :

           32cm                    32cm

 

Step 1: Diameter = 32cm

             Radius = 32 ÷ 2

                          = 16cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 16 x 16 ) - ( 12 x 16 x 16 )

                           = 73.088cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 73.088)

                                 → (π x 16 x 16) - (2 x 73.088)

                                  = 658.176cm2

                                  ≈ 658cm2



10)  

The figure below is formed by two right-angled triangles, a circle and a circle. Given that WX = XY = XZ = 28cm, find the area of the shaded region rounding off your answer to the nearest whole number.

Π = 3.142

         28cm                 28cm

Answer: 504cm2


SOLUTION 1 :

           28cm                    28cm

 

Step 1: Diameter = 28cm

             Radius = 28 ÷ 2

                          = 14cm

Step 2: 12 rugby → quadrant - triangle

                           → ( 14 x π x r2 ) - ( 12 x b x h )

                           → ( 14 x π x 14 x 14 ) - ( 12 x 14 x 14 )

                           = 55.958cm2

Step 3: shaded area → big circle - rugby

                                 → (π x r2) - (2 x 55.958)

                                 → (π x 14 x 14) - (2 x 55.958)

                                  = 503.916cm2

                                  ≈ 504cm2