If the current of the river is 10 miles per hour, what is the speed of the paddle boat in still water? - paddle boat for sale az
A boat ride is 60 miles upstream, at the same time to travel 140 miles downstream.
Paddle Boat For Sale Az If The Current Of The River Is 10 Miles Per Hour, What Is The Speed Of The Paddle Boat In Still Water?
7 comments:
Either the speed of the boat is x miles per hour in calm water
Therefore, as the problem
60 / (x-10) = 140 / (x +10)
=> 3 / (x-10) = 7 / (x +10) [divide both sides by 20]
=> 7x-70 = 3x 30 [by the Cross-Multiplication]
=> 3x = 7x-30 70
=> 4x = 100
x = 25 Therefore the speed of the boat in calm water is 25 mph
distance = rate x time
60 = (S-10) t
140 = (s + 10) t
60 / (S-10) = 140 / (n +10)
Multiply both sides by (S-10) (10 s)
60 s (+10) = 140 (S-10)
60 + 600 years = 140 to 1400
2000 = 80
s = 25 km / h in calm water
Before 60 miles = 60 / 15 = 4 hours
140 miles downstream = 140 / 35 = 4 hours
It varies with the speed and torque used to drive the paddle.
Question.Still trick zero.Boat water does not moving.Up 10 miles per hour, sit, and downstream at 10 miles per hour faster than he moves like a figure from the mainland.
Question.Still trick zero.Boat water does not moving.Up 10 miles per hour, sit, and downstream at 10 miles per hour faster than he moves like a figure from the mainland.
Let X: speed boat in calm water
and the current speed
To travel t: time
(x + y) * T = 140 (below) ... eq.1
(x - y) * T = 60 (top) ... eq.2
by eq.1: x + 10 = 140 / t
x = 140 / t - 10 ... eq.3
by eq.2: x - 10 = 60 / t
x = 60 / T + 10 ... eq.4
Deputy eq.3 in eq.4
140 / t - 10 = 60 / t + 10
(140-60) / T = 10 + 10
80 / t = 20
t = 4
by eq.4: x = 60 / t + 10 = 15 +10 = 25 miles per hour
Let X: speed boat in calm water
and the current speed
To travel t: time
(x + y) * T = 140 (below) ... eq.1
(x - y) * T = 60 (top) ... eq.2
by eq.1: x + 10 = 140 / t
x = 140 / t - 10 ... eq.3
by eq.2: x - 10 = 60 / t
x = 60 / T + 10 ... eq.4
Deputy eq.3 in eq.4
140 / t - 10 = 60 / t + 10
(140-60) / T = 10 + 10
80 / t = 20
t = 4
by eq.4: x = 60 / t + 10 = 15 +10 = 25 miles per hour
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