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denis-greek [22]

3 years ago

5

6. Number of passengers who arrive at the platform in an Amtrack train station for the 2 pm train on a Saturday is a random vari

able with a mean of 180 and a standard deviation of 20. a) With what probability can we assert that there will be between 120 and 240 passengers

1 answer:

Aleks04 [339]3 years ago

4 0

Answer:

99.7%

Step-by-step explanation:

Mean number of passengers (μ) = 180 passengers

Standard deviation (σ) = 20 passengers

The number of standard deviation from the mean for the lower and upper bounds of the 120 to 240 passengers intervals are:

$L = \frac{180-120}{20} =3\\U = \frac{240-180}{20} =3$

Therefore, all of the data is within 3 standard deviations from the mean. According to the empirical rule, 99.7% of the data is within 3 standard deviations from the mean. Therefore, we can assert with a 99.7% probability that there will be between 120 and 240 passengers.

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mars1129 [50]

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Step-by-step explanation:

Given

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$Ratio = 3 : 10 : 7$

Required:

The length of each side

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$S_2 = \frac{10 *180}{20}$

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3 years ago

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lana66690 [7]

Answer:

$h=\frac{\sqrt{3}}{2}b\ units$

Step-by-step explanation:

we know that

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see the attached figure to better understand tyhe problem

Let

h ----> the height of an equilateral triangle

b ---> the length side of an equilateral triangle

In the right triangle ABD

Applying the Pythagorean Theorem

$AB^2=AD^2+BD^2$

substitute the given values

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square root both sides

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7 0

3 years ago