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Rufina [12.5K]
3 years ago
8

Toll booths on the New York State Thruway are often congested because of the large number of cars waiting to pay. A consultant w

orking for the state concluded that if service times are measured from the time a car stops in line until it leaves, service times are exponentially distributed with a mean of 2.7 minutes. What proportion of cars can get through the toll booth in less than 3 minutes?
Mathematics
1 answer:
HACTEHA [7]3 years ago
6 0

Answer:

The proportion of cars can get through the toll booth in less than 3 minutes is 67%.

Step-by-step explanation:

Let the random variable <em>X</em> be defined as the service times at a tool booth.

The random variable <em>X</em> follows an Exponential distribution with parameter <em>μ</em> = 2.7 minutes.

The probability density function of <em>X</em> is:

f_{X}(x)=\frac{1}{\mu}e^{-x/\mu };\ x\geq 0,\ \mu>0

Compute the probability that a car can get through the toll booth in less than 3 minutes as follows:

P(X

                =\frac{1}{2.7}\cdot \int\limits^{3}_{0} {e^{-x/2.7}} \, dx \\\\=\frac{1}{2.7}\cdot [-\frac{e^{-x/2.7}}{1/2.7}]^{3}_{0}\\\\=1-e^{-3/2.7}\\\\=0.6708

Thus, the proportion of cars can get through the toll booth in less than 3 minutes is 67%.

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6 0
2 years ago
A) Use the method of cylindrical shells to find the volume of the solid obtained by rotating the region bounded by the given cur
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3 0
2 years ago
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8 0
2 years ago
Read 2 more answers
What is the value of a?
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8 0
3 years ago
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