A solid metallic cylinder of base radius 3 cm. and height 5 cm. is melted to form cones, each of height 1 cm. and base radius 1 mm. The number of cones is -

If the areas of circular ring having inner and outer radius 8 cm and 12 cm respectively is equal to the total surface area of cylinder of radius R₁ and height h, then h in terms of R₁ will be :

Find the area of triangle whose medians are 8 cm, 15 cm and 17 cm respectively?

The radii of three concentric circles are in the ratio of 4 : 5 : 7. What is the ratio of the area between the two inner circles to that between the two outer circles?

The diagonal of a square is equal to the side of an equilateral triangle. If the area of the square is $$ {18\sqrt{3}}$$ sq.cm. What is the area (in cm²) of the equilateral triangle ?

The diagonal of a square is 14 cm. What will be the length of the diagonal of the square whose area is double of the area of first square?

In a circle of radius 17 cm, two parallel chords of lengths 30 cm. and 16 cm are drawn. If both the chords are on the same side of the center, then the distance between the chords is -

If the ratio of the areas of two similar triangle ABC and DEF is 36:81 and EF = 6.9 cm., then BC is equal to –