Advertisements
Advertisements
प्रश्न
The sum of the length, breadth and depth of a cuboid is 19 cm and its diagonal is ` 5 sqrt(5)` cm. Its surface area is
विकल्प
361 cm2
125 cm2
236 cm2
486 cm2
Advertisements
उत्तर
Let,
l → Length of the cuboid
b → Breadth of the cuboid
h → Height of the cuboid
We have,
l + b + h = 19 cm , diagonal of the cuboid
`( sqrt(l^2 + b^2 +h^2)) = 5 sqrt(5) cm `
We are asked to find the surface area
So, the surface area,
= 2 (lb + bh + hl )
= (l + b +h )2 - ( l2 + b2 + h2 )
`=(l + b+ h) - ( sqrt (l^2 + b^2 + h^2 ))^2`
`=19^2 - (5sqrt(5))^2`
=361-125
=236 cm2
Thus, the surface area is 236 cm2
APPEARS IN
संबंधित प्रश्न
Each edge of a cube is increased by 50%. Find the percentage increase in the surface area of the cube.
A closed iron tank 12 m long, 9 m wide and 4 m deep is to be made. Determine the cost of iron sheet used at the rate of Rs. 5 per metre sheet, sheet being 2 m wide.
A cuboidal block of silver is 9 cm long, 4 cm broad and 3.5 cm in height. From it, beads of volume 1.5 cm3 each are to be made. Find the number of beads that can be made from the block.
Find the volume in cubic metre (cu. m) of the cuboid whose dimensions islength = 4 m, breadth = 2.5 m, height = 50 cm.
The dimensions of a cinema hall are 100 m, 50 m and 18 m. How many persons can sit in the hall, if each person requires 150 m3 of air?
The surface area of a cuboid is 1300 cm2. If its breadth is 10 cm and height is 20 cm2, find its length.
Find the height of the cylinder whose radius is 7 cm and the total surface area is 1100 cm2.
The ratio between the curved surface area and the total surface area of a cylinder is 1: 2. Find the ratio between the height and the radius of the cylinder.
Two cuboids with equal volumes will always have equal surface areas.
