If an equilateral triangle is inscribed in a circle of area 48 π square units, then the perimeter of the triangle is:

The diameter of a circle is equal to the perimeter of a square whose area is 3136 sq cm. What is the circumference of the circle?

The ratio of the areas of two circles is 16: 25. What will be the ratio of their circumferences?

In the given figure, PQRS is square whose side is 8 cm. PQS and QPR are two quadrants. A circle is placed touching both the quadrants and the square as shown in the figure. What is the area ( in cm² ) of the circle ?

A wall is the form of a trapezium with height 8 m and parallel sides being 5 m and 10 m. What is the cost of painting the wall, if the rate of painting is Rs. 50 per square meter  ?

An open box is made of wood 3 cm thick. Its external dimensions are 1.36 m, 1.06 m and 8.3 dm. The cost of painting the inner surface of the box at 50 paise per 100 sq. cm (in Rs.) is 

A field roller, in the shape of a cylinder, has a diameter of 1 meter and length of $$ {1}{1\over4}$$ meter. If the speed at which the roller rolls is 14 revolutions per minute, then the maximum area ( in m²) that it can roll in 1 hour is:

A right circular cylinder is formed by rolling a rectangular sheet of metal of length 44 cm and breath 20 cm along its length. The volume of cylinder is_