हिंदी

Top surface of a raised platform is in the shape of a regular octagon as shown in the figure. Find the area of the octagonal surface. - Mathematics

Advertisements
Advertisements

प्रश्न

Top surface of a raised platform is in the shape of a regular octagon as shown in the figure. Find the area of the octagonal surface.

योग

उत्तर

Area of octagon = Area of (ABDC) + Area of (CDFE) + Area of (EFHG)

= `{1/2 [(5+11) xx 4] + (11 xx 5) + 1/2 [(5 + 11) xx 4]}m^2`

= `{1/2 (16 xx 4) + 55 + 1/2 (16 xx4)}m^2`

= `{1/2 xx 64 + 5 + 1/2 xx 64}m^2`

= {32 + 55 + 32}m2

= 119m2

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 11: Mensuration - Exercise 11.2 [पृष्ठ १७८]

APPEARS IN

एनसीईआरटी Mathematics [English] Class 8
अध्याय 11 Mensuration
Exercise 11.2 | Q 9 | पृष्ठ १७८

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Length of the fence of a trapezium shaped field ABCD is 120 m. If BC = 48 m, CD = 17 m and AD = 40 m, find the area of this field. Side AB is perpendicular to the parallel sides AD and BC.


Find the area, in square metres, of the trapezium whose bases and altitude is as under:
bases = 8 m and 60 dm, altitude = 40 dm


Find the altitude of a trapezium whose area is 65 cm2 and whose bases are 13 cm and 26 cm.


Find the area of a trapezium whose parallel sides of lengths 10 cm and 15 cm are at a distance of 6 cm from each other. Calculate this area as the difference of the area of a rectangle and the sum of the areas of two triangles.


The area of a trapezium is 960 cm2. If the parallel sides are 34 cm and 46 cm, find the distance between them.


The two parallel sides and the distance between them are in the ratio 3: 4: 2. If the area of the trapezium is 175 cm2, find its height.


The area of a trapezium is 279 sq.cm and the distance between its two parallel sides is 18 cm. If one of its parallel sides is longer than the other side by 5 cm, find the lengths of its parallel sides.


Find the area of a trapezium whose parallel sides are 24 cm and 20 cm and the distance between them is 15 cm


A trapezium with 3 equal sides and one side double the equal side can be divided into ______ equilateral triangles of ______ area.


The area of a trapezium with equal non-parallel sides is 168 m2. If the lengths of the parallel sides are 36 m and 20 m, find the length of the non-parallel sides.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×