What is the Normal Distribution of X in Vehicle Speed Observation?

csmumfau
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a vehicle driver gauges the relative speed of the next vehicle ahead by observing the speed with which the image of the width of that vehicle varies. This speed is proportional to X, the speed of variation of the angle at which the eye subtends this width. According to P. Ferrani and others, a study of many drivers revealed X to be normal distributed with a mean of 0 and a standard deviation of 10 ( 10^{-4} radians per sec)

I have no idea how to start, sorry.
 
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csmumfau said:
I have no idea how to start, sorry.

You haven't stated any problem or question.
 
Stephen Tashi said:
You haven't stated any problem or question.

My apologizes.

What fraction of these measurements is more than 5 units away from 0?
 
Have you studied how to rescale the units in problem by converting them to "Z values"? Convert +5 and-5 to Z values by using the scaling. For 5, Z = (5 - mean)/ (standard deviation)
 
Stephen Tashi said:
Have you studied how to rescale the units in problem by converting them to "Z values"? Convert +5 and-5 to Z values by using the scaling. For 5, Z = (5 - mean)/ (standard deviation)

Yeah, I know that but was is sigma? 10 or 10^{-4}
 
csmumfau said:
Yeah, I know that but was is sigma? 10 or 10^{-4}

I'd say it's 10 since the problem asks for "units" and not "radians per second".
 
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