I need help pls! will mark brainliest for the best answer!

Service calls arriving at an electric company follow a Poisson distribution with an average arrival rate of 5656 per hour. Find

liberstina [14]

Answer:

The average number of service calls in a 15-minute period is of 14, with a standard deviation of 3.74.

Step-by-step explanation:

In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

$P(X = x) = \frac{e^{-\mu}*\mu^{x}}{(x)!}$

In which

x is the number of sucesses

e = 2.71828 is the Euler number

$\mu$ is the mean in the given interval. The variance is the same as the mean.

Average rate of 56 calls per hour:

This means that $\mu = 56n$ , in which n is the number of hours.

Find the average and standard deviation of the number of service calls in a 15-minute period.

15 minute is one fourth of a hour, which means that $n = \frac{1}{4}$ . So

$\mu = 56n = \frac{56}{4} = 14$

The variance is also 14, which means that the standard deviation is $\sqrt{14} = 3.74$

The average number of service calls in a 15-minute period is of 14, with a standard deviation of 3.74.

4 0

3 years ago

Suppose that the distance of fly balls hit to the outfield (in baseball) is normally distributed with a mean of 250 feet and a s

Korvikt [17]

Answer:

On the graphing calculator, use the function normCdf, where

lower bound = -9999
upper bound = 210
mean = 250
standard deviation = 46

It will result in normCdf(-9999,210,250,46) ≈ 0.192269 or 19.2269%

6 0

3 years ago

A rental car company is running two specials. Customers can pay $40 to rent a compact car for the first day plus $2 for each add

svp [43]

Answer: 5

Step-by-step explanation:

The equation to solve this problem is 40 + 2x = 25 + 5x

Now, to solve for x you first need to subtract 25 from each side:

15 + 2x = 5x

Next, subtract 2x from each side:

15 = 3x

Finally, divide both sides by 3:

5 = x

Farid is renting the car for 5 additional days.

4 0

3 years ago

A journal article reports that a sample of size 5 was used as a basis for calculating a 95% CI for the true average natural freq

oksano4ka [1.4K]

Answer:

$Lower = 231.134- 3.098=228.036$

$Upper = 231.134+ 3.098=234.232$

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s represent the sample standard deviation

n=5 represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

And for this case we know that the 95% confidence interval is given by:

$\bar X=\frac{233.002 +229.266}{2}= 231.134$

And the margin of error is given by:

$ME = \frac{233.002 -229.266}{2}= 1.868$

And the margin of error is given by:

$ME= t_{\alpha/2} \frac{s}{\sqrt{n}}$

The degrees of freedom are given by:

$df = n-1 = 5-1=4$

And the critical value for 95% of confidence is $t_{\alpha/2}= 2.776$

So then we can find the deviation like this:

$s = \frac{ME \sqrt{n}}{t_{\alpha/2}}$

$s = \frac{1.868* \sqrt{5}}{2.776}= 1.506$

And for the 99% confidence the critical value is: $t_{\alpha/2}= 4.604$

And the margin of error would be:

$ME = 4.604 *\frac{1.506}{\sqrt{5}}= 3.098$

And the interval is given by:

$Lower = 231.134- 3.098=228.036$

$Upper = 231.134+ 3.098=234.232$

6 0

3 years ago

Consider the function. What is the y-intercept of f–1(x)? –16 –12

Mekhanik [1.2K]

<h2>Explanation:</h2><h2></h2>

Hello! Remember you have to write clear questions in order to get good and exact answers. Here, I'll assume the function as:

$f(x)=x^2+2x-16$

The y-intercept of a function is the point at which the graph of the function touches the y-axis. This occurs when we set $x=0$ . In other words, we define the y-intercept (let's call it $b$ as:

$b=f(0)$

Setting $x=0$ in our function we have:

$b=f(0)=(0)^2+2(0)-16 \\ \\ \boxed{b=f(0)=-16}$

So <em>in this context the y-intercept is -16</em>

7 0

3 years ago