Question
A motor boat covers a certain distance downstream in a
river in 1 hour. It covers the same distance upstream in 1 hour and 30 minutes. If the speed of water is 3 km/h, then the speed of the boat in still water is:Solution
Let the speed of boat in still water be x km/hr and the distance be y km. Rate downstream = (x + 3) km/hr Rate upstream = (x – 3) km/hr According to the question, y/(x + 3) = 1 --- (i) y/(x – 3) = 3/2 --- (ii) On dividing equation (i) by (ii), (x – 3)/(x + 3) = 1/(3/2) = 2/3 3x – 9 = 2x + 6 x = 9 + 6 = 15 kmph
Which type of soil has swelling and shrinking property?
Equivalent acidity of Ammonium sulphate fertilizer is-
In the context of insect pest management, under which of the following conditions would the sterile-male technique be least effective?
In which layer of the Earth's atmosphere do various meteorological phenomena such as different types of clouds, thunderstorms, cyclones, and anti-cyclon...
The minimum isolation distance for production of certified seed of composite Maize is -
Estimates of National Income in India are annually prepared by:
The particle size of "clay" is -
A crop sown with another crop to gain some advantage in yield are termed as
Saline soils can be improved by –
Which of the following chemical is used to break the dormancy of potato seeds?
