Question 949545
Downstream rate=rate of boat+rate of river
Upstream rate=rate of boat-rate of river
Let b=rate of boat and r=rate of river
24mph=b+r Subtract b from each side
24 mph-b=r
10mph=b-r Substitute for r from above
10 mph=b-(24 mph-b)
10 mph=b-24mph+b Add 24 mph to each side
34 mph=2b Divide each side by 2.
17 mph=b ANSWER 1: The rate of the boat in still water is 17 mph.
r=24mph-b=24mph-17mph=7 mph ANSWER 2:The rate of the river is 7 mph