Question
A boat travels the same distance 'd' km in both upstream
and downstream directions, taking a total of 15 hours for the round trip. If the downstream speed of the boat is 16 km/hr and the upstream speed is 8 km/hr, calculate the time required for the boat to cover '1.5d' km in still water.Solution
ATQ, d/16 + d/8 = 15 Or, {d + 2d)/16} = 15 Or, 3d = 15 X 16 Or, 3d = 240 So, 'd' = (240/3) = 80 Speed of boat in still water = average of speed of boat in downstream and in upstream = (16 + 8)/2 = 12 km/hr  So, required time = 80 x 1.5/12 = 10 hrsÂ
- A square has a side length equal to the radius of a circle whose area is 201.96 m². Calculate the perimeter of the square.
The radius of a circle is equal to the radius of base of a cone. If the diameter of the circle is 35 cm and the height of cone is 18 cm, then find the v...
(190/3)% of the raindrops could have been collected, when 2 cm of rain has fallen on a part of land of area 3 km2, in a tank having a 200 m &...
The radius of a sphere is 75% of the radius of a cylinder, while the height of the cylinder is 25% greater than its radius. Determine the ratio of the v...
A cylinder has a height of 14 cm and a radius of 7 cm. Find the total surface area.
A closed wooden box of uniform thickness has length, breadth and height 20cms, 16cms and 12 cms respectively. If the thickness of the wooden block is 2 ...
A cylindrical tank has a height of 10 meters and a radius of 7 meters. What is the volume of the tank?
The perimeter of a rhombus is 130 m. If one of its diagonals is 16 m, then the area of the rhombus is
The perimeter of a rectangle of length 2(x + 5) cm and breadth 2(x + 2) cm is double the perimeter of a square of area 324 cm². Find the area of the re...
- If the edge of the cube is increased by 5%, then find the percentage increase in the volume of the cube.