Question
Area of a rectangle is equal to the total surface area
of a hemisphere having volume 4394 cm³ . Find the perimeter of the rectangle if its length is 125% more than its breath. (Take π = 3)Solution
Let, the radius of the hemisphere be ‘r’ cm. So according to question: 2/3 × 3 × r3 = 4394 r3 = 2197 r = 13 So, the total surface area of the hemisphere = 3 × π × 13² = 3 × 3 × 13² = 1521 cm² Let the breadth of the rectangle be ‘x’ cm So the length of the rectangle = 2.25x cm According to question: x × 2.25x = 1521 x² = 676 x = 26 So the breadth of the rectangle = 26 cm Length of the rectangle = 26 × 2.25 = 58.5 cm So the perimeter of the rectangle = 2 × (58.5 + 26) = 169 cm
The base of a right prism is a regular hexagon of side 5 cm. If its height is 12 √3 cm, then its volume (in cm²) is:
A pyramid has a square base with a height of 12 cm. Each of the pyramid's faces is an equilateral triangle, and the area of each face is 64√3 cm². Fi...
A rectangular lawn 25m x 30m has two roads each 6 metres wide, running in the middle of it, one parallel to the length and the other parallel to the bre...
Length and breadth of a rectangle are in the ratio 5:4. If the perimeter of the rectangle is 52 cm more than the length of the rectangle, then find the ...
A pipe fills a cubical tank at the rate of 242 m3Â per minute in 44 minutes. If a cylindrical tank having height same as the side of a cubica...
- Seven cubes, each of edge 7 cm, are attached in a row to make a cuboid. Find its total surface area.
On a rectangular wall of length 22 metres and height 19 metres, there is a window in the shape of triangle surmounted on a square. If the base of triang...
The ratio of the length of a rectangle, breadth of the rectangle and the diameter of a circle is 14:5:7. If the area of the circle is 616 cm2...
The area of a square is 100 cm2 which is 160 cm2 less than that of a rectangle. Find the perimeter of the rectangle if the length ...
A race track is in the shape of a rectangle with length of 70 metres and area of 4900 m2. A car takes 5 seconds to make one lap around the pe...