Question

A rectangular sheet of plastic is 40cm by 25 cm. From it 50 circular badges each of diameter

Answer 1

To find :

 We have to find the diameter of each circular badge made out of the rectangular sheet of plastic of 40 cm by 25 cm.

Formula :

  Area of a rectangle = length × breadth

  Area of circle = πr²

Step by step solution :

The area of the rectangular sheet

        = 40 × 25 cm²

        = 1000 cm²

Let, the radius of each circular badge is r cm

So, area of a circular badge

   = πr² cm²

50 badges are made, so total area of 50 badges

   = 50πr² cm²

Here, 50πr² = 1000

 or, πr² = 20

 or, 22/7 * r² = 20

 or, r² = 20 * 7 /22

 or, r² = 70/11

Thus, r ≈ 2.5 cm

         Diameter of a circular badge

         = 2r cm

         = 2 * 2.5 cm

         = 5 cm