For the following questions answer them individually
The radii of two cylinders are in the ratio 2 : 3 and their heights are in the ratio 5 : 3. The ratio of their volumes is
Three cubes of iron whose edges are 6cm, 8cm and 10cm respectively are melted and formed into a single cube. The edge of the new cube formed is
The radii of two concentric circles are 68 cm and 22 cm. The area of the closed figure bounded by the boundaries of the circles is
The radius of a sphere is 6 cm. It is melted and drawn into a wire of radius 0.2 cm. The length of the wire is
The radius of a wire is decreased to one-third. If volume remains the same, length will increase by
In a trapezium ABCD, AB and DC are parallel sides and $$\angle ADC = 90^\circ$$. If AB = 15 cm, CD = 40 cm and diagonal AC = 41 cm. Then the area of the trapezium ABCD is
The cost of levelling a circular field at 50 Paise per square metre is Rs 7700. The cost (in Rs) of putting up a fence all round it at Rs 1.20 per meter is ( Use $$\pi = \frac{22}{7}$$)
From the four corners of a rectangular sheet of dimensions 25 cm $$\times$$ 20 cm, square of side 2 cm is cut off from four corners and a box is made. The volume of the box is
The height and the total surface area of a right circular cylinder are 4 cm and $$8\pi$$ sq.cm. respectively. The radius of the base of cylinder is