SOLUTION: It tok Sally 3 hours to go 75 miles down stream and it took her 5 hours to travel back upstream to her starting position. What was the speed of her boat in still water and what wa
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Question 66552This question is from textbook Advanced mathematics
: It tok Sally 3 hours to go 75 miles down stream and it took her 5 hours to travel back upstream to her starting position. What was the speed of her boat in still water and what was the speed of the current in the river? This question is from textbook Advanced mathematics
You can put this solution on YOUR website! It tok Sally 3 hours to go 75 miles down stream and it took her 5 hours to travel back upstream to her starting position. What was the speed of her boat in still water and what was the speed of the current in the river?
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Let b be boat speed; Let c be current speed
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Down Stream DATA:
distance=75 miles ; time= 3 hrs ; rate= 75/3=35 mph
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Up Stream DATA:
distance=75 miles ; time= 5 hrs ; rate = 75/5=15 mph
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EQUATIONS:
b+c=35 mph
b-c=15 mph
Add to get:
2b=50
b=25 mph (boat speed)
b+c=25+c=35
c=10 mph (current speed)
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Cheers,
Stan H.
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