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Q:
A) 1.8h | B) 3h |
C) 4h | D) 5h |
Answer: B) 3h
Explanation:
Explanation:
Upstream speed = B-S
Downstream speed = B+s
B-S = 15/5 = 3 km/h
Again B= 4S
Therefore B-S = 3= 3S
=> S = 1 and B= 4 km/h
Therefore B+S = 5km/h
Therefore, Time during downstream = 15/5 = 3h