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
The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of Rs 7.50 per m2.
A cuboidal block of solid iron has dimensions 50 cm, 45 cm and 34 cm. How many cuboids of size 5 cm by 3 cm by 2 cm can be obtained from this block? Assume cutting causes no wastage.
The rainfall on a certain day was 6 cm. How many litres of water fell on 3 hectares of field on that day?
If the volumes of two cubes are in the ratio 8: 1, then the ratio of their edges is
The number of cubes of side 3 cm that can be cut from a cuboid of dimensions 10 cm × 9 cm × 6 cm, is ______.
Four cubes, each of edge 9 cm, are joined as shown below :
Write the dimensions of the resulting cuboid obtained. Also, find the total surface area and the volume
The total surface area of a cylinder is 6512 cm2 and the circumference of its bases is 88 cm. Find:
(i) its radius
(ii) its volume
The length, breadth, and height of a rectangular solid are in the ratio 6 : 4 :3. If the total surface area is 1728 cm2. Find its dimensions.
A room is 22m long, 15m broad and 6m high. Find the area of its four walls and the cost of painting including doors and windows at the rate of Rs.12per m2.
Find the length of the largest pole that can be placed in a room of dimensions 12 m × 4 m × 3 m.
