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Thepotemich [5.8K]

4 years ago

15

A pleasure boat sets out for a cruise on a river, sailing upstream 24 miles and then turning around and returning to port. The t

rip upstream requires 144 minutes and the trip downstream requires 40 minutes. Find the speed of the boat in still water and the speed of the current in miles per hour (mi/h). Round to the nearest whole number.

1 answer:

sineoko [7]4 years ago

4 0

Answer:

V(w) = 26 miles/hour

Step-by-step explanation:

Let

V(bu) upstream boat speed V(w) water speed

Speed upstream

V(bu) = 24 /144 ⇒ V(b) = 0,167 miles/min

V(bd) = 24/40 V(bd) = 0,6 miles/min

V(bd) = V(b) + V(w)

0,6 -0,167 = V(w)

V(w) = 0,433 miles/min

or equivalent in miles /hour

V(w) = 25.98 miles/hour

V(w) = 26 miles/hour

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