The length of a hollow thick cylindrical metallic pipe is 6 cm and its total surface area including the surface at the ends is 98π sq. cm. If the outer diameter is 8 cm, then the inner diameter in cm is 

A regular hexagon has a side of 4 cm. Find its area. (in sq. cm)

The ratio between the length and breadth of a rectangular park is 3: 2. If a man cycling along the boundary of the park at the speed of 12 Km./hr. completes one round in 8 min, then the area of the park in sq.m is – 

The length, breadth and height of a room is 21 metres, 12 metres and 16 metres. What will be the length of the largest rod that can be placed in that room?

A shuttlecock used of playing badminton has the shape of a frustum of a cone mounted on a semi sphere. The external diameters of the frustum are 5 cm and 2 cm, the height of the entire shuttlecock is 7 cm. The external surface is of the shuttlecock is:

The ratio of the areas of two isosceles triangles having the same vertical angle is 1 : 9.The ratio of their heights is -

A semicircle is folded to make a cone. Find the height (in cm) of the cone if diameter of the semicircle is 28 cm?

The length of a rectangle is 6 cm more than its width and its perimeter is 100 cm. If the area of this rectangle is closest to the area of a circle, then what is the circumference of that circle?