Answer:
- boat speed: 17.25 mph
- current: 2.5 mph
Step-by-step explanation:
Upstream, the speed of the current (c) subtracts from the speed of the boat (b) to give the net speed. Downstream, the speed of the current adds. We can make use of the relation ...
speed = distance/time
b-c = 29.5/2 = 14.75 . . . . . miles/hour
b+c = 59.25/3 = 19.75 . . . .miles/hour
Subtracting the first equation from the second, we get ...
(b+c) -(b-c) = 19.75 -14.75
2c = 5
c = 2.5
Then either equation can be used to find b:
b = 14.75 +c = 17.25
The speed of the boat in still water is 17.25 miles per hour; the speed of the current is 2.5 miles per hour.
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