Question

The speeds of vehicles on a highway with speed limit 90 km/h are normally distributed with mean 101 km/h and standard deviation 6 km/h. (Round your answers to two decimal places.)

(a) What is the probability that a randomly chosen vehicle is traveling at a legal speed?

(b) If police are instructed to ticket motorists driving 115 km/h or more, what percentage of motorist are targeted?

Answer #1

The speeds of vehicles on a highway with speed limit 90 km/h are
normally distributed with mean 102 km/h and standard deviation 10
km/h. (Round your answers to two decimal places.)
(a) What is the probability that a randomly chosen vehicle is
traveling at a legal speed?
(b) If police are instructed to ticket motorists driving 110
km/h or more, what percentage of motorist are targeted?

Thank you in advance!
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A traffic study conducted on an interstate highway shows that
vehicle speeds (in mph) are normally distributed with a mean of
61.3 and a standard deviation of 3.3.
a) Sketch the distribution of vehicle speeds.
Show 3 steps of standard deviation above and below the mean.
b) If a vehicle is randomly checked, what is the
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sketch.
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The
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