Question

a certain yacht takes the same amount of time to travel 66 km downstream as it takes to travel 41 km find the approximate speed of current if the speed of yacht in still water is 39 km per hr

Answer 1

Given info : a certain yacht takes the same amount of time to travel 66 km downstream as it takes to travel 41 km. the speed of yacht in still water is 39 km/h.

To find : the approximate speed of current is..

solution : let speed of current is x km/h

for downstream, speed = (39 + x) km/h

for upstream, speed = (39 - x) km/h

a/c to question,

time taken to travel 66km in downstream = time taken to travel 41 km in upstream

⇒66/(39 + x) = 41/(39 - x)

⇒66/41 = (39 + x)/(39 - x)

⇒(66 + 41)(66 - 41) = (39 + x + 39 - x)/(39 + x - 39 + x)

⇒107/25 = 78/2x = 39/x

⇒x = 39 × 25/107 = 9.11 ≈ 9 km/h

Therefore the approximate speed of current is 9 km/h

Answer 2

Answer:

Hope it help you

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