ICSE ICSE Class 8 - CISCE Question Bank Solutions for Mathematics

The area of a circle is 1386 sq.cm; find its circumference.

Find the area of a flat circular ring formed by two concentric circles (circles with the same centre) whose radii are 9 cm and 5 cm.

Cost of 24 identical articles is Rs. 108, Find the cost of 40 similar articles.

If 15 men can complete a piece of work in 30 days, in how many days will 18 men complete it?

Find the area of the shaded portion in each of the following diagrams:

(i)

(ii)

In order to complete a work in 28 days, 60 men are required. How many men will be required if the same work is to be completed in 40 days?

The radii of the inner and outer circumferences of a circular running track are 63 m and 70 m respectively. Find :
(i) the area of the track ;
(ii) the difference between the lengths of the two circumferences of the track.

A fort had provisions for 450 soldiers for 40 days. After 10 days, 90 more soldiers come to the fort. Find in how many days will the remaining provisions last at the same rate?

A circular field of radius 105 m has a circular path of uniform width of 5 m along and inside its boundary. Find the area of the path.

A garrison has sufficient provisions for 480 men for 12 days. If the number of men is reduced by 160; find how long will the provisions last?

There is a path of uniform width 7 m round and outside a circular garden of diameter 210 m. Find the area of the path.

A wire, when bent in the form of a square; encloses an area of 196 cm². If the same wire is bent to form a circle; find the area of the circle.

The radius of a circular wheel is 42 cm. Find the distance travelled by it in :
(i) 1 revolution ;
(ii) 50 revolutions ;
(iii) 200 revolutions ;

The diameter of a wheel is 0.70 m. Find the distance covered by it in 500 revolutions. If the wheel takes 5 minutes to make 500 revolutions; find its speed in :
(i) m/s
(ii) km/hr.

If 12 men or 18 women can complete a piece of work in 7 days, in how many days can 4 men and 8 women complete the same work?

A bicycle wheel, diameter 56 cm, is making 45 revolutions in every 10 seconds. At what speed in kilometre per hour is the bicycle traveling?

If 3 men or 6 boys can finish a work in 20 days, how long will 4 men and 12 boys take to finish the same work?

A roller has a diameter of 1.4 m. Find :
(i) its circumference ;
(ii) the number of revolutions it makes while travelling 61.6 m.

A piece of wire of length 108 cm is bent to form a semicircular arc bounded by its diameter. Find its radius and area enclosed.

In the following figure, a rectangle ABCD enclosed three circles. If BC = 14 cm, find the area of the shaded portion (Take π = 22/7)