Question 173619
rate of the boat = 33 mph.
rate of the water = c miles per hour.
t = amount of time it takes to go upstream = amount of time it takes to go downstream.
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rate * time = distance
going upstream (against the current), the equation is:
(33-c) * t = 300
going downstream (with the current), the equation is:
(33+c) * t = 360
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remove parentheses in both equations:
33*t - c*t = 300
33*t + c*t = 360
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add both equations together to remove c*t.
66*t = 660
t = 10
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substitute 10 for t in the first equation:
33*10 - c*10 = 300
330 - c*10 = 300
subtract 300 from both sides of equation to get:
30 - c*10 = 0
add c*10 to both sides of equation to get:
30 = c*10
divide both sides of equation by 10 to get:
3 = c
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substitute 10 for t and 3 for c in the second equation to get:
33*10 + 3*10 = 360
330 + 30 = 360
360 = 360
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equations are good.
answer is:
current is traveling at 3 miles per hour.