A train covers a distance from station A… | Answer

Subject

Quantitative Aptitude

Topic

Speed & Distance

A train covers a distance from station A to station B at the speed of 58 kmph and covers the distance from station B to station A at the speed of 52 kmph. What is the approximate average speed of the train?
Reading

ক)

54kmph

খ)

58kmph

গ)

48kmph

ঘ)

52kmph

ঙ)

64kmph

Explanation

Distance from station A to station B = x km (say) The train covers the distance from station A to station B at the speed of 58 kmph At this speed, the train covers x km in (x/58) hours. Similarly, the train covers station B to station A in (x/52)hours Hence, the train covers 2x km distance in [(x/58)+(x/52)]hours [(x/58)+(x/52)] = 0.036x In 0.036x hours the train goes 2x km In 1 hour the train goes 2x/0.036x = 54 km (approximately) SHORT TRICK: The average of two speeds over equal distances is obtained using their harmonic means:

\frac{{2{\rm{\;}} \times {\rm{\;}}58{\rm{\;}} \times {\rm{\;}}52}}{{58 + 52}} = \frac{{58 \times 52}}{{55}} = 54.83

≈ 54kmph

A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is:Speed of a boat in standing water is 9 kmph and the speed of the stream is 5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:two trains are moving in opposite directions at 60 km/hr and 90 km/hr. Their lengths are 1/10 km and 9 km respectively. The time taken by slower train to cross the faster train in seconds is -A man can row three-quarters of a kilometre against the stream in 11×(1/4) minutes and down the stream in 7×(1/2) minutes. The speed (in km/hr) of the man in still water is:In a 300 m race A beats B by 5 metre or 6 seconds. B's time over the course is -A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minutes. How long will it take to go 5 km in stationary water?A boat covers a certain distance downstream in 1 hour, while it comes back in 1x(1/2) hours. If the speed of the stream be 3 kmph, what is the speed of the boat in still water?A man buys tk 20 shares paying 9% dividend. The man wants to have an interest of 12% on his money. The market value of each share is-

A train covers a distance from station A to station B at the speed of 58 kmph and covers the distance from station B to station A at the speed of 52 kmph. What is the approximate average speed of the train?Reading

A train covers a distance from station A to station B at the speed of 58 kmph and covers the distance from station B to station A at the speed of 52 kmph. What is the approximate average speed of the train?

Explanation

Related questions

Find Tutors

A train covers a distance from station A to station B at the speed of 58 kmph and covers the distance from station B to station A at the speed of 52 kmph. What is the approximate average speed of the train?
Reading