A, B and three men can finish a work in 10, 20 and 15 days respectively, then in how many days will all three together finish the work?

A boat goes 10kms an hour in still water, but takes twice as much time in going the same distance against the current. The speed of the current (in km/hr) is 

Find the equation of the line that passing through the point (7, -5 ) and is perpendicular to  the line (4x+5y=1).

The ratio of the sides of a triangle is 3: 4: a and the area of this triangle is 216 square cm. And the perimeter of this triangle is 72 cm. Then the value of a will be -

The areas of the three adjacent faces of a cuboid are 32 cm², 24 cm² and 48cm². What is the volume of the cuboid?

The diagonal of a square is equal to the side of an equilateral triangle. If the area of the square is sq.cm. What is the area (in cm²) of the equilateral triangle ?

Speed of a boat in still water is 6 km/hr and speed of the current is 2 km/hr. If boat takes four hours more in upstream than in the downstream to cover ‘D’ km, then find time take by boat to cover ‘D’ km in still water?

25.6% of 250 +√ ? = 119