Question 958122: How many revolution per second will an automobile wheel make at the rate of 63.4km per hour if the diameter is 5.4dm??p
Found 3 solutions by lwsshak3, ikleyn, MathTherapy:
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! How many revolution per second will an automobile wheel make at the rate of 63.4km per hour if the diameter is 5.4dm??p
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notes:
circumference=π*diameter=π*5.4 dm
dm=decimeter
meter=10 decimeters
kilometer=1000 meters
Answer by ikleyn(53937)  (Show Source):
You can put this solution on YOUR website! .
How many revolutions per second will an automobile wheel make at the rate of 63.4km per hour
if the diameter is 5.4dm ?
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This is a simple arithmetic problem, but the answer "1957 revolutions per second"
given in the post by @lwsshar3 is absolutely absurdist.
Not only the answer, but his approach in whole and his method are
absolutely inappropriate for the solution and for teaching.
He concentrates on deriving very long formula, which is not needed,
instead of concentrating on the problem's meaning. As a result, he was not able
to solve the problem correctly.
See below my correct solution, as it should be done by a 5-th or 6-th grade student.
The diameter of the wheel is d = 5.4 decimeters, or d = 54 centimeters.
Hence, the circumference of the wheel is  =  = 169.65 cm.
The car moves forward 63.4 km per hour, or  = 17.61 meters per second, or 1761 centimeters per second.
From it, the number of revolutions per second is the ratio  = 10.38, approximately.
ANSWER. The number of revolutions per second is 10.38.
Solved correctly.
As I read this post by @lwsshar3, it proves to me once again, for the 1001st time, that this person does not read
what his computer code produces.
Answer by MathTherapy(10858)  (Show Source):
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