The speed of a boat in still water is 60kmph and the speed of the current is 20kmph. Find the speed downstream and upstream?
Correct answer: B. 80, 40 kmph
- A. 35, 25 kmph
- B. 80, 40 kmph
- C. 40, 60 kmph
- D. 50, 55 kmph
Explanation
Downstream motion adds the current speed to the still-water speed, so 60 km/hr + 20 km/hr = 80 km/hr. Upstream motion subtracts it, so 60 km/hr - 20 km/hr = 40 km/hr. The likely mistake is option c, which reverses the order and gives 40 km/hr downstream and 60 km/hr upstream.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Time, Speed and Distance
Problems relate distance, speed and time through the formula distance = speed × time, including unit conversion, average speed, relative speed and motion in opposite or the same direction. Questions may involve trains, boats and streams, where the effective speed changes, so average speed must not be confused with the simple average of two speeds.
Practise Arithmetic
1,060 free Arithmetic MCQs from Mathematics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Mathematics questions like this
Mathematics is on 76 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Time, Speed and Distance questions
The speed of a boat in upstream is 60 kmph and the speed of the boat downstream is 80 kmph. Find the speed of the boat in still water and the speed of the stream?
A man rows his boat 85 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?
A man can row a boat at 20 kmph in still water. If the speed of the stream is 6 kmph, what is the time taken to row a distance of 60 km downstream?
The current of a stream at 1 kmph. A motor boat goes 35 km upstream and back to the starting point in 12 hours. The speed of the motor boat in still water is_________?
A man whose speed is 4.5 kmph in still water rows to a certain upstream point and back to the starting point in a river which flows at 1.5 kmph, find his average speed for the total journey?
The current of a stream runs at the rate of 4 kmph. A boat goes 6 km and back to the starting point in 2 hours, then find the speed of the boat in still water?