ICSE ICSE Class 8 - CISCE Question Bank Solutions

Solve the inequation `("2x" + 1)/3 + 15 ≤ 17;` x ∈ W.

Solve the inequation -3 + x < 2, x ∈ N.

Solve: 4x - 5 > 10 - x, x ∈ {0, 1, 2, 3, 4, 5, 6, 7}.

The length, breadth, and height of a cuboid are in the ratio 5 : 3: 2. If its volume is 240 cm³; find its dimensions. Also, find the total surface area of the cuboid.

Solve: 15 – 2(2x – 1) < 15, x ∈ Z.

Solve: `("2x" + 3)/5 > ("4x" - 1)/2`, x ∈ W.

The length, breadth, and height of a cuboid are in the ratio 6: 5 : 3. If its total surface area is 504 cm²; find its dimensions. Also, find the volume of the cuboid.

Find the volume and total surface area of a cube whose each edge is:
(i) 8 cm
(ii) 2 m 40 cm.

Find the length of each edge of a cube, if its volume is :
(i) 216 cm³
(ii) 1.728 m³

The total surface area of a cube is 216 cm2. Find its volume.

A solid cuboid of metal has dimensions 24 cm, 18 cm, and 4 cm. Find its volume.

A wall 9 m long, 6 m high and 20 cm thick, is to be constructed using bricks of dimensions 30 cm, 15 cm, and 10 cm. How many bricks will be required?

A solid cube of edge 14 cm is melted down and recast into smaller and equal cubes each of the edge 2 cm; find the number of smaller cubes obtained.

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.

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

How many persons can be accommodated in a big-hall of dimensions 40 m, 25 m, and 15 m; assuming that each person requires 5 m³ of air?

The dimension of a class-room are; length = 15 m, breadth = 12 m and height = 7.5 m. Find, how many children can be accommodated in this class-room; assuming 3.6 m³ of air is needed for each child.

The length, breadth, and height of a room are 6 m, 5.4 m, and 4 m respectively. Find the area of :
(i) its four-walls
(ii) its roof.

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.

The dining-hall of a hotel is 75 m long; 60 m broad and 16 m high. It has five – doors 4 m by 3 m each and four windows 3 m by 1.6 m each. Find the cost of :

(i) papering its walls at the rate of Rs.12 per m²;
(ii) carpetting its floor at the rate of Rs.25 per m².