Subject: General Aptitude · Chapter: Boats and Streams · Exam: · Marks: · Difficulty:
The speed of a motor boat is that of the current of water as 36 : 5. The boat goes along with the current in 5 hours 10 minutes. How much time will it take to come back? (S.S.C., 2007)
Answer
Answer (as printed):
Explanation
Let the speed of the motor boat and that of the current be 36x km/hr and 5x km/hr respectively. Then, speed downstream = (36x + 5x) km/hr = 41x km/hr. Speed upstream = (36x – 5x) km/hr = 31x km/hr. Let the distance be d km. d 10 1 31 31 × 41 1271x Then, =5 =5 = ⇒ d= x= . 41x 60 6 6 6 6 d 1271x 1 41 5 \ Time taken while coming back = = × hrs = hrs = 6 hrs 31x 6 31x 6 6 = 6 hrs 50 min.
Explanation as extracted from the printed page; notation may be imperfect.