Question
If the speed of stream is 3 km/h, a boat takes 9 hours
to travel 112 km downstream and 110 km upstream. What is the speed (in km/h) of the boat in still water?Solution
Given: Stream speed = 3 km/h Downstream: 112 km Upstream: 110 km Total time = 9 hours Let boat speed in still water = x km/h Downstream speed = x + 3 Upstream speed = x − 3 Time = Distance / Speed 
Multiply both sides by (x + 3)(x − 3): 
Solve using quadratic formula: 
Which of the following is not true for geometric mean?
Which of the following statement is true for NRR?
Which of the following is not a cause of rightward shift of demand curve?
A systematic sample does not yield good result, if -
Infant mortality rate is the ratio of -
Which of the following is a second-order condition of short-run equilibrium of firm under perfect competition?
Which of the following is yearly publication of CSO?
A population is said to be stationary, if -
If Q₁, Q₂ and Q₃ are three quartiles of a frequency distribution, which of the following holds if the distribution is negatively skewed?
...Which of the following is Non-governmental Statistical Organisation?
