6 An umbrella is made by stitching 10 triangular pieces of cloth of tw

1.	6 An umbrella is made by stitching 10 triangular pieces of cloth of twodifferent colours(see Fig. 12.16), each piece measuring 20 cm, 50 cm and 50 cm. How much cloth of eachcolour is required for the umbrella?
Answer» For pieces of triangle, a = 20 cm , b = 50 cm , c = 50 cm .°. s = a + b + c / 2 = 20 + 50 + 50 / 2 = 120 / 2 = 60 cm .°. a triangles area = √ s ( s - a ) ( s - b ) ( s - c ) = √ 60 ( 60 - 20 ) ( 60 - 50 ) ( 60 - 50 ) = √ 60 ( 40 ) ( 10 ) ( 10 ) = 200√6 cm² .°. one colour of five triangles area , = 5 ( 200√6 ) cm² = 1000√6 cm² so, there are 1000√6 cm² cloth of each colour is required for the umbrella very Nice

6 An umbrella is made by stitching 10 triangular pieces of cloth of twodifferent colours(see Fig. 12.16), each piece measuring 20 cm, 50 cm and 50 cm. How much cloth of eachcolour is required for the umbrella?

Answer»

For pieces of triangle,

a = 20 cm , b = 50 cm , c = 50 cm

.°. s = a + b + c / 2

= 20 + 50 + 50 / 2

= 120 / 2

= 60 cm

.°. a triangles area = √ s ( s - a ) ( s - b ) ( s - c )

= √ 60 ( 60 - 20 ) ( 60 - 50 ) ( 60 - 50 )

= √ 60 ( 40 ) ( 10 ) ( 10 )

= 200√6 cm²

.°. one colour of five triangles area ,

= 5 ( 200√6 ) cm²

= 1000√6 cm²

so, there are 1000√6 cm² cloth of each colour is required for the umbrella

very Nice