answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Vikentia
2 months ago
9

The number of tickets purchased by an individual for Beckham College's holiday music festival is a uniformly distributed random

variable ranging from 2 to 7. Find the mean and standard deviation of this random variable. (Round your answers to 2 decimal places.) Mean Standard deviation
Mathematics
1 answer:
Inessa [12.5K]2 months ago
7 0

Answer:

The average is 4.5 and the standard deviation measures 1.44.

Step-by-step explanation:

A uniform probability distribution is one where every outcome is equally probable.

This situation defines a lower limit we call 'a' and an upper limit referred to as 'b.'

The average of the uniform probability distribution is expressed as:

M = \frac{(a + b)}{2}

The standard deviation associated with this distribution is calculated as:

S = \sqrt{\frac{(b-a)^{2}}{12}}

This represents a uniformly distributed random variable spanning from 2 to 7.

This implies that a = 2, b = 7.

Hence

M = \frac{(2 + 7)}{2} = 4.5

S = \sqrt{\frac{(b-a)^{2}}{12}} = \sqrt{\frac{(7 - 2)^{2}}{12}} = 1.44

The mean is 4.5 and the standard deviation is 1.44.

You might be interested in
The manufacturer of hardness testing equipment uses steel-ball indenters to penetrate metal that is being tested, however, the m
Inessa [12570]

Answer:

1.667-2.31\frac{1.803}{\sqrt{9}}=0.2789  

1.667+2.31\frac{1.803}{\sqrt{9}}=3.055  

Based on the analysis, the 95% confidence interval is specified as (0.2789;3.055)  

The question regarding the 95% confidence interval's ability to ascertain potential differences in measurements between the two indenters is as follows:

Indeed, the confidence interval does not include the value 0, thus indicating that the Diamond values significantly exceed those of the Steel Ball at a 5% significance level.

Step-by-step explanation:

Here is the dataset in consideration:

specimen    1     2    3     4      5     6     7    8     9

Steel Ball   51   57   61   70   68   54   65  51   53

Diamond   53   55  63   74   69   56   68  51   56

By calculating the differences between diamond and steel ball measurements, we create the dataset:

d: 2, -2, 2, 4, 1, 2, 3, 0, 3

In the next step, we compute the mean difference  

\bar d= \frac{\sum_{i=1}^n d_i}{n}=1.667

Following that, we determine the standard deviation of the differences, arriving at:

s_d =\frac{\sum_{i=1}^n (d_i -\bar d)^2}{n-1} =1.803

A confidence interval refers to "a range of values that’s likely to encompass a population value with a certain level of confidence. It is typically expressed as a percentage indicating where a population mean falls within an upper and lower limit."  

The margin of error represents the extent to which values diverge above and below the sample statistic in a confidence interval.  

Normal distribution, is described as a "probability distribution that is symmetric about the mean, illustrating that data points close to the mean occur more frequently than those further away."  

The confidence interval for the mean is derived using the following formula:  

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

To calculate the critical value t_{\alpha/2}, we first determine the degrees of freedom using:  

df=n-1=9-1=8  

Given a confidence level of 0.95 or 95%, the appropriate critical value can be found using Excel, a calculator, or a table. The Excel command would be: "=-T.INV(0.025,9)". Therefore, we observe that t_{\alpha/2}=2.31.

Finally, we can substitute all our findings into formula (1):  

1.667-2.31\frac{1.803}{\sqrt{9}}=0.2789  

1.667+2.31\frac{1.803}{\sqrt{9}}=3.055  

In this case, the 95% confidence interval is calculated as (0.2789;3.055)  

In determining if the two indenters yield distinct measurements, we find that the confidence interval does not enclose zero, allowing us to conclude that Diamond readings greatly surpass Steel Ball readings at the 5% significance level.

4 0
17 days ago
You can upgrade lighting at your factory to LED bulbs that cost $6.95 each and last an average of 5 years. It costs $3 in labor
Inessa [12570]
Each LED bulb, along with installation labor, is priced at
.. $6.95 +$3 = $9.95

For 100 bulbs over a span of 10 years, that equals (100*10) = 1000 bulb·years. At $9.95 per bulb, 5 bulb·years are obtained, and thus the projected total cost for 1000 bulb·years is
.. (1000 b·y)*($9.95/(5 b·y)) = $1990

In summary, for a decade, the installation and changes of 200 bulbs in 100 lamps amount to $1990. Therefore, the yearly cost is...
.. $1990/(10 yr) = $199/yr
3 0
1 month ago
Read 2 more answers
The name of the lesson is "Using Trigonometric Laws" The two non-parallel sides of an isosceles trapezoid are each 7 feet long.
AnnZ [12381]
The diagonal measures 20.68 ft; the shorter base is 17.21 ft. To understand this, we recognize that with base angles summing to 140°, each angle is 70°, given the isosceles trapezoid's properties. We can apply the Law of Cosines to find the diagonal's length, denoted as d. The length of the diagonal determines to be d = 20.68 ft. Determining the shorter base is somewhat more complex. By drawing an altitude from the upper vertices to the base, which measures 22 ft, we create two similar smaller right triangles requiring us to find the height and base measures related to each of the 70-degree angles and the hypotenuse of 7. By working through the calculations for height and base from one triangle, we subsequently find that 22 minus twice the base measure gets us to the shorter base's measure, arriving at x = 17.21 ft.
4 0
26 days ago
Given the function f(x) = −5x2 − x + 20, find f(3). −28 −13 62 64
Leona [12618]

Answer:

Option (a) is the correct choice.

The result of the given function f(x)=-5x^2-x+20 at x = 3 is -28

Detailed explanation:

Provided: Function f(x)=-5x^2-x+20

We need to calculate the function's value at x = 3

Evaluate the specified function f(x)=-5x^2-x+20

As we are required to find the function's value at x = 3

Substitute x = 3 into the function f(x)

f(3)=-5(3)^2-(3)+20

Upon simplification, we get

f(x)=-45-3+20=-28

Thus, the value of the given function f(x)=-5x^2-x+20 at x = 3 is -28

5 0
23 days ago
Read 2 more answers
9. Apply The number of people in the United States who are at least 100
zzz [12365]
In 1980, if there were N individuals aged 100 or older, then by 2010, the number grew to N*1.66 for those 100 and above. A straightforward conditional expression can be framed as: If P, then Q, where P represents the hypothesis and Q is the conclusion. We understand that "The count of individuals aged 100 years or older increased by about 66% from 1980 to 2010," meaning that if we had N individuals aged 100 or older in 1980, we will have N*(166%/100%) = N*1.66 in 2010, allowing us to write a conditional statement: If there were N individuals aged 100 years old in 1980, then by 2010, we had N*1.66 individuals who were at least 100 years old.
8 0
1 month ago
Other questions:
  • Stefan's family rented a rototiller to prepare an area in their backyard for spring planting. The rental company charged an init
    5·2 answers
  • A line contains points M(1, 3) and N(5, 0). What is the slope of MN? negative StartFraction 4 Over 3 EndFraction negative StartF
    13·2 answers
  • A teacher wants to see if a new unit on factoring is helping students learn. She has five randomly selected students take a pre-
    10·1 answer
  • Ratio for 669 and 221
    6·2 answers
  • How many solutions does the equation sin(5x) = 1/2 have on the interval (0, 2PI]
    11·1 answer
  • The length of a rectangle is measured as 370mm correct to 2 significant figures.
    8·1 answer
  • Carla can choose two of her three pairs of sneakers to take to a track meet. If the pairs of sneakers are called A, B, and C, wh
    14·2 answers
  • Which represents the solution set to the inequality 5.1(3 + 2.2x) > –14.25 – 6(1.7x + 4)?
    8·2 answers
  • A sociologist wishes to see if it is true that for a certain group of professional women, the average age at which they have the
    12·1 answer
  • What is the true solution to In 20+In 5= 2 In x?<br><br>#31<br>​
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!