Subject
Quantitative Aptitude
Topic
Boat and Stream
A swimmer sims from a point A against a current for 5 minutes and then swims backwards in favour of the current for next 5 minutes and comes to the point B. If AB is 100 meters, the speed of the current (in km per hour) is :
A swimmer sims from a point A against a current for 5 minutes and then swims backwards in favour of the current for next 5 minutes and comes to the point B. If AB is 100 meters, the speed of the current (in km per hour) is :
ক)
0.4খ)
0.2গ)
1ঘ)
0.6Explanation
The swimmer swims from A to C in upstream, C to A in downstream and A to B in downstream So, The swimmer swims x distance in upstream for 5 min. And, From C to B the swimmer swims ( x + 100 ) distance in downstream for next 5 min . upstream speed, u + v = {x/(5/60)} = 12x ......(i) downstream speed, u - v = {(x+100)/(5/60)} = 12(x+100) = u - L = 12x + 1200 .....(ii) (i) - (ii) u + v - u + v = 12x - 12x - 1200 => 2L = -1200 => v = 600 m/hr = 600/1000 km/hr = 0.6 km/hrRelated questions
স্থির পানিতে একটি নৌকার গতিবেগ ৮ কিলোমিটার এবং স্রোতের প্রতিকূলে ওই নৌকার গতিবেগ ৫ কিলোমিটার হলে স্রোতের গতি ও স্রোতের অনুকূলে ওই নৌকার গতিবেগ কতA boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.In one hour, a boat goes 11 km/hr along the stream and 5 km/hr against the stream. The speed of the boat in still water (in km/hr) is:The speed of a boat in still water in 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes 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 man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is:If a boat goes 7 km upstream in 42 minutes and the speed of the stream is 3 kmph, then the speed of the boat in still water is: (যদি একটি নৌকা স্রোতের প্রতিকূলে 42 মিনিটে 7 কি. মি. যায় এবং স্রোতের গতি 3 কি. মি./ঘন্টা হয়, তাহলে স্থির পানিতে নৌকার বেগ কত?)The ages of Samina and Suhana are in the ratio of 7:3 respectively. After 6 years, the ratio of their ages will be 5:3. What is the difference in their ages ? (সামিনা ও সুহানার বয়সের অনুপাত 7:3 । 6 বছর পরে তাদের বয়সের অনুপাত হবে 5:3 । তাদের বয়সের পার্থক্য কত ?)