Subject
Quantitative Aptitude
Topic
Speed & Distance
A man can row at 7 km/hour in still water. He finds that it takes twice the time to row upstream than the time to row downstream. The speed of the stream is
A man can row at 7 km/hour in still water. He finds that it takes twice the time to row upstream than the time to row downstream. The speed of the stream is
ক)
2.6 km/hourখ)
7 km/hourগ)
2.3 km/hourঘ)
4 km/hourExplanation
The speed of the stream is y km/hour (say) Hence upstream speed will be (7-y) km/hour And downstream speed will be (7+y)km/hour it takes twice the time to row upstream than the time to row downstream. Hence, speed of downstream is twice than the speed of upstream. According to the problem, 7+y = 2(7-y) ⇒7+y = 14 – 2y ⇒3y = 7 ⇒y = 2.33 Speed of the stream = 2.33 km/hourRelated questions
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