SOLUTION: Hi, i can't seem to work out this question, please help me... A boat sails against the stream and after 2 hours it has moved 10km. If the boat sails wlt the stream it would have mo
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Question 753152: Hi, i can't seem to work out this question, please help me... A boat sails against the stream and after 2 hours it has moved 10km. If the boat sails wlt the stream it would have moved 30km in 2 hours. Determine the the velocity of the boat and the velocity of the stream. Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! A boat sails against the stream and after 2 hours it has moved 10km. If the boat sails wlt the stream it would have moved 30km in 2 hours. Determine the the velocity of the boat and the velocity of the stream.
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Let x = velocity of boat
and y = velocity of stream
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since we have two unknowns, we'll need two equations:
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applying the distance formula of:
d = rt
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From:"A boat sails against the stream and after 2 hours it has moved 10km."
10 = 2(x-y)
dividing both sides by 2:
5 = x-y (equation 1)
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From:"If the boat sails wlt the stream it would have moved 30km in 2 hours."
30 = 2(x+y)
dividing both sides by 2:
15 = x+y (equation 2)
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Adding the two equations together:
5 = x-y
15 = x+y
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20 = 2x
10 km/hr = x (velocity of boat)
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substitute above into equation 2:
15 = x+y
15 = 10+y
5 km/hr = y (velocity of stream)
