ICSE ICSE Class 8 - CISCE Question Bank Solutions for Mathematics

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.

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.

A closed box measures 66 cm, 36 cm and 21 cm from outside. If its walls are made of metal-sheet, 0.5 cm thick; find :
(i) the capacity of the box ;
(ii) the volume of metal-sheet and
(iii) weight of the box, if 1 cm³ of metal weighs 3.6 gm.

Find the area of metal-sheet required to make an open tank of length = 10 m, breadth = 7.5 m and depth = 3.8 m.

A tank 30 m long, 24 m wide, and 4.5 m deep is to be made. It is open from the top. Find the cost of iron-sheet required, at the rate of ₹ 65 per m², to make the tank.

The internal length, breadth, and height of a closed box are 1 m, 80 cm, and 25 cm. respectively. If its sides are made of 2.5 cm thick wood; find :
(i) the capacity of the box
(ii) the volume of wood used to make the box.

The capacity of a rectangular tank is 5.2 m³ and the area of its base is 2.6 x 104 cm²; find its height (depth).

State which of the following are polygons :

(i)

(ii) 

(iii)  

(iv)

(v)

(vi)

If the given figure is a polygon, name it as convex or concave.

Write the degree of a polynomial of the following:

xy + 7z

Write the degree of a polynomial of the following:

x² − 6x³ + 8

Write the degree of a polynomial of the following:

y − 6y² + 5y⁸

Write the degree of a polynomial of the following:

xyz − 3

Write the degree of a polynomial of the following:

xy + yz² − zx³

Write the degree of a polynomial of the following:

x⁵y⁷ – 8x³y⁸ + 10x⁴y⁴z⁴

The figure, given below, shows a pentagon ABCDE with sides AB and ED parallel to each other, and ∠B : ∠C : ∠D = 5: 6: 7.

(i) Using the formula, find the sum of the interior angles of the pentagon.

(ii) Write the value of ∠A + ∠E

(iii) Find angles B, C and D.

In parallelogram ABCD, ∠A = 3 times ∠B. Find all the angles of the parallelogram. In the same parallelogram, if AB = 5x – 7 and CD = 3x +1 ; find the length of CD.

In parallelogram PQRS, ∠Q = (4x – 5)° and ∠S = (3x + 10)°. Calculate: ∠Q and ∠R.