Advertisements
Advertisements
Question
A room 5 m long, 4.5 m wide, and 3.6 m high have one door 1.5 m by 2.4 m and two windows, each 1 m by 0.75 m. Find :
(i) the area of its walls, excluding door and windows ;
(ii) the cost of distempering its walls at the rate of Rs.4.50 per m2.
(iii) the cost of painting its roof at the rate of Rs.9 per m2.
Advertisements
Solution
Length of the room = 5 m
The breadth of the room = 4.5 m
Height of the room = 3.6 m
Area of the roof = `"L" xx "B"`
= `5 xx 4.5`m2
= 22.5 m2
Area of four walls = 2[L + B] × H
= 2[5 + 4.5] × 3.6
= 2(9.5) × 3.6
= 19 × 3.6
= 68.4 m2
Area of one door = `1.5 xx 2.4 "m"^2`
= 3.60 m2
= 3.6 m2
Area of one window = `1 xx 0.75`m2
= 0.75 m2
Area of 2 window = `0.75 xx 2`m2
= 1.5 m2
(i) Area of four walls excluding door and windows = 68.4 - (3.6 + 1.5)
= 68.4 - 5.1
= 63.3 m2
(ii) Cost of distempering four walls @ Rs. 4.50 per m2
= 63.3 × 4.50
= Rs. 284.85
(iii) Cost of painting the roof @ Rs.9 per m2
= 22.5 × 9
= Rs. 202.50
APPEARS IN
RELATED QUESTIONS
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.
Find the lateral surface area and total surface area of a cube of edge 10 cm.
An open box is made of wood 3 cm thick. Its external length, breadth and height are 1.48 m, 1.16 m and 8.3 m. Find the cost of painting the inner surface of Rs 50 per sq. metre.
A wooden bookshelf has external dimensions as follows: Height = 110 cm, Depth = 25 cm, Breadth = 85 cm in following figure. The thickness of the plank is 5 cm everywhere. The external faces are to be polished and the inner faces are to be painted. If the rate of polishing is 20 paise per cm2 and the rate of painting is 10 paise per cm2. Find the total expenses required for polishing and painting the surface of the bookshelf.

A cuboidal vessel is 10 cm long and 5 cm wide. How high it must be made to hold 300 cm3 of a liquid?
Three cuboids of dimensions 5 cm × 6 cm × 7cm, 4cm × 7cm × 8 cm and 2 cm × 3 cm × 13 cm are melted and a cube is made. Find the side of cube.
How many bricks each of size 25 cm × 10 cm × 8 cm will be required to build a wall 5 m long, 3 m high and 16 cm thick, assuming that the volume of sand and cement used in the construction is negligible?
An 8 m long cuboidal beam of wood when sliced produces four thousand 1 cm cubes and there is no wastage of wood in this process. If one edge of the beam is 0.5 m, find the third edge.
A solid rectangular piece of iron measures 6 m by 6 cm by 2 cm. Find the weight of this piece, if 1 cm3 of iron weighs 8 gm.
The dimensions of an oil tin are 26 cm × 26 cm × 45 cm. Find the area of the tin sheet required for making 20 such tins. If 1 square metre of the tin sheet costs Rs 10, find the cost of tin sheet used for these 20 tins.
A cuboid has total surface area of 50 m2 and lateral surface area is 30 m2. Find the area of its base.
If V is the volume of a cuboid of dimensions a, b, c and S is its surface area, then prove that \[\frac{1}{V} = \frac{2}{S}\left( \frac{1}{a} + \frac{1}{b} + \frac{1}{c} \right)\]
Find the edge of a cube whose surface area is 432 m2.
If each edge of a cube, of volume V, is doubled, then the volume of the new cube 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 ______.
If l is the length of a diagonal of a cube of volume V, then
The external dimensions of a closed wooden box are 27 cm, 19 cm, and 11 cm. If the thickness of the wood in the box is 1.5 cm; find:
- The volume of the wood in the box;
- The cost of the box, if wood costs Rs. 1.20 per cm3;
- A number of 4 cm cubes that could be placed into the box.
The volume of a cuboid is 3456 cm3. If its length = 24 cm and breadth = 18 cm ; find its height.
Find the volume and total surface area of a cube whose each edge is:
(i) 8 cm
(ii) 2 m 40 cm.
A closed box is cuboid in shape with length = 40 cm, breadth = 30 cm and height = 50 cm. It is made of a thin metal sheet. Find the cost of metal sheet required to make 20 such boxes, if 1 m2 of metal sheet costs Rs. 45.
Find the volume of wood required to make a closed box of external dimensions 80 cm, 75 cm, and 60 cm, the thickness of walls of the box being 2 cm throughout.
The length, breadth, and height of a cuboid (rectangular solid) are 4 : 3: 2.
(i) If its surface area is 2548 cm2, find its volume.
(ii) If its volume is 3000 m3, find its surface area.
The curved surface area and the volume of a toy, cylindrical in shape, are 132 cm2 and 462 cm3 respectively. Find, its diameter and its length.
Find the Total Surface Area and the Lateral Surface Area of a cuboid whose dimensions are: length = 20 cm, breadth = 15 cm, height = 8 cm
The surface area of a cuboid formed by joining face to face 3 cubes of side x is 3 times the surface area of a cube of side x.
