Question
Pipes P and Q alone can fill a tank in 6 hours and 3
hours respectively. When both pipes along with pipe R, an outlet pipe, are opened together, 2/5 of the tank gets filled in 60 minutes. Find the time taken by pipe R to empty a completely filled tank.Solution
Let the total capacity of the tank be 30 litres.
Efficiency of Pipe 'P' = 30 / 6 = 5 litres/hour
Efficiency of Pipe 'Q' = 30 / 3 = 10 litres/hour
Let pipe 'R' empties the tank with an efficiency of 'm' litres/hour.
Tank filled in 60 minutes = (2/5) × 30 = 12 litres
ATQ,
(5 + 10 - m) × (60/60) = 12
(15 - m) × 1 = 12
15 - m = 12
m = 3 litres/hour
Time taken by R to empty the tank = 30 / 3 = 10 hours
The length of a rectangle is 8 cm less than the radius of a circle. The perimeter of the rectangle is 60 cm, and the ratio of its length to breadth is 4...
A circular wire of diameter 56 cm is folded in the shape of a rectangle whose sides are in the ratio 6:5. Find the area enclosed by the rectangle.
If ratio of interior & exterior angle of a regular polygon is 5:3, then number of sides of the polygon is
- Find the diameter of the incircle of a triangle whose semi-perimeter is 18 cm and area is 54 cm².
If perpendicular and base of a right-angle triangle are 30 cm and 40 cm respectively, then find the length of the shortest median of triangle.
The capacity of a cylindrical tank is 2376 m³. If the radius of the tank is 21 m, then the depth of the tank is:
The ratio of males and females in a zoo is 6:7 respectively and the percentage of children among males and the percentage of children among females are ...
A rectangular park is 50 m long and 30 m wide. A path of uniform width 2 m is built inside along all sides of the park. Find the area of the path.
Four circles of equal radii are described about the four corners of a square so that each touches two of the other circles. If each side of the square i...
A rectangular piece of copper foil of length 63 cm and area 1386 cm2 is folded along its width to form a cylinder such that there is only one...
Relevant for Exams:
