-
A boy can swim in still water at a speed of 10 km/hr. If the speed of the current would have been 5 kmph, then the boy could swim 60km
-
- upstream in 4 hour
- downstream in 12 hours
- upstream in 6 hours
- downstream in 4 hours
- upstream in 4 hour
Correct Option: D
Given that , Speed of boy = 10 km/hr
Speed of the current = 5 kmph
∴ Rate downstream = Speed of boy + Speed of the current
Rate downstream = 10 + 5 = 15 kmph
Rate upstream = 10 – 5 = 5 kmph
Time taken in swimming 60km downstream = 60 ÷ 15 = 4 hours
Time taken in swimming 60km upstream = 60 ÷ 5 = 12 hours
From, given options, boy can swim 60km downstream in 4 hrs.
