Question
Speed of a boat in still water to speed of boat in
upstream is 7:5. If the boat can travel 360 km in downstream in 5 hours, then find the time taken by the boat to cover 28 km in still water.Solution
Let speed of boat in still water and speed of boat in upstream be ‘7x’ km/h and ‘5x’ km/h, respectively. Speed of stream = 7x – 5x = 2x km/h Speed of boat in downstream = 7x + 2x = 9x km/h So, 9x = 360/5 = 72 Or, x = 8 Speed of boat in still water = 7 × 8 = 56 km/h Desired time = 28/56 = 30 minutes
Who was the author of ‘Kathasaritsagar’?
Due to ocean acidification, when the ocean becomes more acidic, what happens to the pH level of the ocean?
A train can cross a pole in 48 seconds. While if the train increased its speed by 50% then time taken by it to cross 225 metres long platform is 42 seco...
The sum of three numbers is 136. If the ratio between the first number and the second number is 2 : 3 and that between the second and the third number i...
Which of the following countries does not have a coastline?
Any employer employing 100 or more workers intending to close down must give notice:
Which of the following statement is/are incorrect regarding “Trade Union Act 1926”?
I. The need for a legal framewor...
30 men can complete a piece of work in 48 days. ‘x’ men started the work and after 33 days 64 more men joined them so that whole work was finished i...
The Kuki people are an ethnic group of which of the following North Eastern states?
Amit has 7 friends whom he wishes to invite to a dinner. Out of his 7 friends, 1 or more may accept the invitation. In how many different ways can Amit...
Relevant for Exams:
