Length and breadth of a rectangular sheet of paper are 20cm and 10cm,

1.	Length and breadth of a rectangular sheet of paper are 20cm and 10cm, respectively. A rectangular piece is cut from the sheet as shown in Fig.. Which of the following statements is correct for the remaining sheet?
Answer» (A) Perimeter remains same but area changes. We know that, area of big rectangle = length × breadth = 10 × 20 = 200 cm² Area of small rectangle = 5 × 2 = 10 cm² Perimeter of rectangle = 2(length + breadth) = 2(20 + 10) = 2 × 30 = 60 cm Then, perimeter of new figure = 20 + 8 + 5 + 2 + 15 + 10 = 60 Area of new figure = Area of big rectangle – Area of new figure = 200 – 10 = 190 cm² By comparing all the results, Perimeter remains same but area changes.

Length and breadth of a rectangular sheet of paper are 20cm and 10cm, respectively. A rectangular piece is cut from the sheet as shown in Fig.. Which of the following statements is correct for the remaining sheet?

Answer»

(A) Perimeter remains same but area changes.

We know that, area of big rectangle = length × breadth

= 10 × 20

= 200 cm²

Area of small rectangle = 5 × 2

= 10 cm²

Perimeter of rectangle = 2(length + breadth)

= 2(20 + 10)

= 2 × 30

= 60 cm

Then, perimeter of new figure = 20 + 8 + 5 + 2 + 15 + 10

= 60

Area of new figure = Area of big rectangle – Area of new figure

= 200 – 10

= 190 cm²

By comparing all the results, Perimeter remains same but area changes.