Listen NCERT Audio Books - Kitabein Ab Bolengi
An umbrella is made by stitching 12 triangular pieces of cloth, each measuring (50 cm x 20 cm x 50 cm). Find the area of the cloth used in it.
Let the sides of the triangle be,
a = 50 cm
b = 20 cm
And
C = 50 cm
Now, let us find the value of s:
s =
=
= 60 cm
We know that,
Area =
Area of one triangular piece of cloth =
=
=
=
= 10 × 10 × 2
= 200
= 200 × 2.45
= 490 cm2
Therefore,
Area of one piece of cloth = 490 cm2
Hence,
Area of 12 pieces of cloth = 12 × 490
= 5880 cm2