Question
A motor boat goes downstream from point A to B ,which is
36 km away from point A, and then returns to A. If actual speed of the boat in still water is 7 km/hour , and the total upstream and downstream journey takes 21 hours .What must be the actual speed of boat for the journey from A to B to take exactly 108 minutes?Solution
Speed of boat in still water is 7km/hour Let the Speed of Stream be x Km/hour 36/(7+x) + 36/(7-x) = 21 24 = 49- x2 x = 5 km/hour Now, the speed of Boat for the journey from A to B to take time 108 minutes is Speed of boat = y km/hour , Speed of stream =5km/hour , Time = 108 minutes (y+5) = (36×60)/108 = 20km/hour y+5 = 20 y = 15 km/hour ∴ Speed of Boat must be 15 km/hour.
Azolla is used in cultivation of:
The part of the wing which is triangular in shape and has the humeral, apical, and anal angles is known as
Conversion of organic form of nitrogen into inorganic form is refer to as………………..
Curry leaf isÂ
Scientific name of desert locust is _______:
The Black soil which are found in the area of Maharashtra, Gujrat, M.P. have the dominant clay mineral i.e.
Which is the most suitable method for preserving flowers with high moisture content like roses and carnations?
Harvest index of 19% (lowest among pulses) is observed in which crop?Â
Which among the following fungicides is non-systemic?
Dendrobium orchid belongs to the familyÂ
Relevant for Exams:
