Math, Ch-12 PERIMETER AND AREA

 February 11,2021

Topic taught : Perimeter and Area(Ex.- 12.1)

Q1.

Ans a. 2cm + 2cm + 1cm + 1cm + 1cm+ 3cm= 10 cm

Ans b. 4cm + 2cm + 4cm + 2cm = 12 cm

Ans c. 1cm + 1cm + 2cm + 1cm +1cm + 2cm+ 4cm + 2cm= 14 cm

Ans d. 1cm + 1cm + 1cm + 1cm= 4cm

Ans e. 3cm + 1cm + 1cm + 2cm +1cm +2cm +1cm+1cm = 12cm

Ans f. 2cm + 3cm +2cm +3cm = 10cm

Ans g. 2cm + 1cm +1cm + 1cm +1cm +1cm + 1cm +2cm +1cm + 1cm= 12cm

Ans h. 2cm + 2cm + 2cm + 2cm = 8cm

Q2

Ans a. Perimeter = 3cm + 4cm + 2cm + 4cm = 13cm

Ans b. Perimeter = 2cm +2cm +2cm +2cm +2cm +2cm = 12cm

Ans c. Perimeter = 4cm + 5cm + 3cm = 12cm

Ans d. Perimeter = 2cm + 2cm + 1cm + 3cm +4cm = 12cm

Ans e. Perimeter = 4cm + 3cm + 4cm +4cm + 3cm = 18cm

Ans f. Perimeter = 3cm + 3cm + 2cm +3cm + 5cm + 3cm  =19cm

Q3

Ans a. Perimeter of rectangle = PQ + QR + RS + PS

                                                  = 8cm + 5cm + 8cm + 5cm 

                                                 = 26cm

Ans b. Perimeter of Square = LM + MO + ON + LN

                                               = 7cm + 7cm + 7cm + 7cm

                                               = 28cm

Ans c. Perimeter of Triangle = GI + IH + HG

                                                 = 8cm + 7cm + 5cm= 20cm

Q4

Ans a. Perimeter of square = 4x side

                                               = 4x 2

                                               = 8cm

Ans b. Perimeter of square = 4x side

                                              = 4x 3

                                              = 12cm

Ans d. Perimeter of rectangle  = length + breadth + length + breadth

                                                    = 4cm +2cm + 4cm + 2cm = 12cm

Ans e. Perimeter of rectangle  = length + breadth + length + breadth

                                                    = 5m + 1m + 5m + 1m = 12m

Ans g. Perimeter of triangle = side + side + side

                                                = 3cm + 4cm + 7cm = 14cm

Ans i. Perimeter of triangle = side + side + side

                                                = 5cm + 5cm + 5cm = 15 cm

Q5

Ans a. Length of the mobile , l= 10cm

            Breadth of the mobile, b= 6cm

           Perimeter of the mobile = 2x(l + b)

                                                   = 2x( 10 + 6)

                                                 = 2x 16 = 32 cm

Therefore, the perimeter of mobile is 32cm.

Ans b. Length of the garden = 65 m

           Breadth of the garden = 65 -20 = 45m

           Perimeter of the garden = 2x(l + b)

                                                    =2x(65 + 45)

                                                    =2x110 = 220m

     Therefore, Perimeter of the rectangular garden is 220m.

Ans c.  Perimeter of the swimming pool = 1km

           Srinath went around the swimming pool = 3 times

           Total distance Srinath walk = 1km x 3times

                                                           = 3 km.

Ans d. Side of the Square garden = 25m

             Perimeter of the square = 4x side

                                                      = 4x 25 = 100 m

Therefore Mr. Gupta will have to purchase 100m of wire.

Note : Complete the Exercise 12.1 in Math notebook.

Home work : Q3 - d , Q4 - c, f, h  and Q5 - e

Kindly Submit the worksheet of Ch- Measurement and Time on Betweenus.

Ignore if already submitted.