The average of 5 consecutive natural numbers is M. If the next three natural numbers are also included, how much more than M will the average of these 8 numbers be? 

The area of a circle is proportional to the square of its radius. A small circle of radius 3 cm is drawn within a larger circle of radius 5 cm. Find the ratio of the difference between the area of the larger circle and that of the smaller circle to the area of the larger circle.

Find the area of the circle formed in an equilateral triangle of side 42 cm. Using (π=22/7)

The line graph shows the number of vacancies of accountants in a certain company. Study the diagram and answer the following questions.

Between which two years is the rate of decrement in vacancies is maximum?

If the sum of first three natural numbers from a group of six consecutive natural numbers is 36, then the sum of last three natural numbers will be? 

According to an instruction a mixture of colour and Turpentine containing half part of each is perfect for painting a wall. A painter is provided a mixture, 3 parts of which are colour and 5 parts are Turpentine. How much of the mixture drawn off and replaced with colour so that the mixture becomes perfect?

The difference between the selling prices of an article at a profit of 15% and at a profit of 10% is Rs.10. The cost price of the article is -

The angle of elevation of the top of a tower from a point A on the ground is 30^o. On moving a distance of 20 m towards the foot of the tower to a point B, the angle of elevation increase to 60^o.The height of the tower is-