Assume the random variable X is normally distributed, with mean = 54 and standard deviation o = 8. Find the 15th percentile.

Answers

Answer 1

Answer:

45.712

Step-by-step explanation:

We need to find the Zscore of the area of 15 percent of the distribution ; using a Z table or calculator ;

Zscore of 15% of the distribution is : - 1.036

Using the Zscore formula :

Zscore = (x - mean) / standard deviation

Where, x = score

-1.036 = (x - 54) / 8

Cross multiply

-1.036 * 8 = x - 54

-1.288 = x - 54

x = - 8.288 + 54

x = 45.712


Related Questions

Find the Taylor series for f(x) centered at the given value of a. (Assume that f has a power series expansion. Do not show that Rn(x)→0 . f(x)=lnx, a=

Answers

Answer:

Here we just want to find the Taylor series for f(x) = ln(x), centered at the value of a (which we do not know).

Remember that the general Taylor expansion is:

[tex]f(x) = f(a) + f'(a)*(x - a) + \frac{1}{2!}*f''(a)(x -a)^2 + ...[/tex]

for our function we have:

f'(x) =  1/x

f''(x) = -1/x^2

f'''(x) =  (1/2)*(1/x^3)

this is enough, now just let's write the series:

[tex]f(x) = ln(a) + \frac{1}{a} *(x - a) - \frac{1}{2!} *\frac{1}{a^2} *(x - a)^2 + \frac{1}{3!} *\frac{1}{2*a^3} *(x - a)^3 + ....[/tex]

This is the Taylor series to 3rd degree, you just need to change the value of a for the required value.

5* 2+3.(4+2)-4(5* 2)

Answers

Answer:

5 * 2 + 3(4 + 2) - 4(5 * 2)

= 10 + 3(6) - 4(10)

= 10 + 18 - 40

= 28 - 40

= -12

What is the following product? Assume x>0 and y>0 v5x^8y^2•v10^3•v12y

Answers

Answer:

[tex]10x^{5}y \sqrt{6xy}[/tex]

Step-by-step explanation:

If someone can pls give me the answer the would be greatly appreciated :)

Answers

Step-by-step explanation:

The Answer Is Provided Below ➳

(2²)² = 2⁴/2⁴ = 2⁰ × 2⁰ = 2⁰/2⁰

Not sure about the answers I gave

Need help with the others

Answers

Answer:

Ask me

Step-by-step explanation:

Tell me dear ask..

Create a quadratic equation in one variable of the form ax^2+bx+c=0 that meets the following criteria. A=1, b=0 , c=-100. 20 points.

Answers

Answer:

Equation is x^2-100=0

Step-by-step explanation:

I'm assuming everything is in standard form. Just plug in the values.

1(x)^2+(0)x+(-100)=0

0 times x is 0, so it simplifies to

x^2-100=0

Find the missing term in the following pattern.


1984, 992, 496, blank space, 124, 62

Answers

Answer:

248

Step-by-step explanation:

common ratio for two consecutive terms is 2/1

for eg: 1984÷992 =2

992÷ 496 = 2

124÷ 62 = 2

that means 124 ×2 = 248 Answer

the answer is 248. good luck!

How do I solve this. Y=f(x)+a moves the function

Answers

Answer:

up

Step-by-step explanation:

for linear functions, adding a constant will increase the y value by two and shift the line up two units on the graph.

Answer: It moves the function 'a' units up if a > 0. Or it moves the function |a| units down if a < 0.

Explanation:

Consider an example like y = f(x)+2. This shifts the f(x) curve 2 units up because we're adding 2 to each y or f(x) output. A point like (5,7) shifts up to (5,9).

As another example, y = f(x)-5 moves the curve 5 units down.

In the first example, we had a > 0 which moved the function 'a' units up (a = 2 in that case). The second example had a = -5 which means a < 0, so that's why we shifted |a| = |-5| = 5 units down.

For each of the following variables, identify the type of variable (categorical vs. numeric). (1) Temperature (in Fahrenheit) of an office building (11) Traffic congestion (e.g. light, medium, heavy)
1) (1) Numeric, and (II) Categorical
2) (1) Numeric, and (II) Numeric
3) (1) Categorical, and (II) Numeric
4) There is no correct match.
5) (1) Categorical, and (11) Categorical

Answers

Answer:

(a) Temperature: Numerical

(b) Traffic congestion: Categorical

Step-by-step explanation:

Required

Determine the variable type

(a) Temperature

Temperatures are measured in numeric values e.g. 22 degree Fahrenheit, etc.

Hence, the variable is numerical

(b) Traffic congestion

From the question, we understand that the traffic congestion are divided into three categories i.e. light, medium....

Hence, the variable is categorical

g In the year 2005, the age-adjusted death rate per 100,000 Americans for heart disease was 222.3. In the year 2009, the age-adjusted death rate per 100,000 Americans for heart disease had changed to 213.4. a) Find an exponential model for this data, where t

Answers

This question is incomplete, the complete question is;

In the year 2005, the age-adjusted death rate per 100,000 Americans for heart disease was 222.3. In the year 2009, the age-adjusted death rate per 100,000 Americans for heart disease had changed to 213.4.

a) Find an exponential model for this data, where t = 0 corresponds to 1999

Answer:

the exponential model for this data will be; y = 222.3( 0.9898 )^t

Step-by-step explanation:

Given the data in the question;

{ 2005 }, at t = 0, death rate was 222.3

In 2009, { 2009 - 2005 = 4 }, at t = 4 death rate was 213.4

Now, let the exponential equation be;

y = ab^(t)

so at t = 0

222.3 = a × b^(0)

222.3 = a × 1

a = 222.3

at t = 4

213.4 = a × b^(4)

213.4 = 222.3 × b^(4)

b⁴ = 213.4 / 222.3

b = (  213.4 / 222.3 )^(1/4)

b = 0.9898

y = ab^(t)

Hence, the exponential model for this data will be; y = 222.3( 0.9898 )^t

Find the area enclosed by y1 = (x - 1)3 and y2 = x -1.

I wanted to double check the answer. The professor got something completely different.

Find area between two curves

Answers

9514 1404 393

Answer:

  0.5

Step-by-step explanation:

The "enclosed area" can be taken to mean different things. Here, we consider it to mean the finite area bounded between the two curves, regardless of which curve is higher value than the other.

The area is bounded on the interval [0, 2]. On half that interval y1 > y2; on the other half, y2 > y1. This means the integral of the area between the curves will be different for one part of the interval than for the other. (The curves are symmetric about the point (1, 0).)

The area on the interval [0, 1] is given by the integral ...

  [tex]\displaystyle\int_0^1{(y_1-y_2)}\,dx=\int_0^1{((x-1)^3-(x-1))}\,dx\\\\=\int^1_0{(x(x-1)(x -2))}\,dx=\left.(\frac{x^4}{4}-x^3+x^2)\right|^1_0=\boxed{\frac{1}{4}}[/tex]

The area on the interval [1, 2] is the integral of the opposite integrand, but has the same value.

The positive area over the whole interval from 0 to 2 is 1/4+1/4 = 1/2.

If you simply integrate y2-y1 or y1-y2 over that interval, the result is 0.

Which choice is equivalent to the expression below?
V -100
O A. 110;
B. 101
C. -10
O D. 10
O E. - V10

Answers

Answer:

C. -10

Step-by-step explanation:

[tex]hope \: it \: helps[/tex]

CarryOnLearning

Pls help! Answer the question

Answers

Answer:  74 inches

===============================================================

Explanation:

The given stem and leaf plot leads to this data set

68,68,69,69

71,72,77,77,78,78

80,81

I broke it up to have each tens digit get its own row. That way it's bit more readable.

Unfortunately, the term "average" in math is very vague. It could mean one of the following

meanmedianmode

To get the mean (specifically the arithmetic mean), we will add up the values and then divide by n = 12 because there are 12 values in the list above. Adding said values gets us

68+68+69+69+71+72+77+77+78+78+80+81 = 888

Dividing that over 12 then leads to 888/12 = 74

The arithmetic mean is 74.

-------------

To get the median, we would first sort the data set. Though that is already done for us. From here, we locate the middle-most item.

Since there are n = 12 items here, the middle item is between slot n/2 = 12/2 = 6 and slot 7

The values in slots 6 and 7 are 72 and 77 respectively. The midpoint of those values is (72+77)/2 = 149/2 = 74.5

The median is 74.5

-------------

The mode is possibly the quickest measure of center or average we can compute. We simply look at the value that shows up the most. In this case, the following values show up twice (which is the most frequent of all the values)

68697778

They are all tied for the title of "mode". It's possible to have more than one mode, so we say the mode is the set {68,69,77,78}.

Due to the nature of multiple modes, the mode is often not a good measure of center (but it's still a possibility; especially for categorical data).

In this case, I think the mean or median is a better measure of center.

Since there aren't any outliers, the mean is the best measure of center in this case. Luckily, the mean and median (74 and 74.5 respectively) are fairly close to one another.

-------------

To summarize everything, the term "average" is too vague and it could refer to the mean, median or mode. In this problem, the mean is possibly the best measure of center since there aren't any outliers and the mode isn't one single value.

We found the following:

mean = 74median = 74.5mode = {68,69,77,78}

It's very likely your teacher is wanting the mean.

8) If 150% of a number is 75, then what is the 80% of that number?
A. 40
B. 50
C. 70
D. 85

Answers

Answer:

A. 40

Step-by-step explanation:

Answer:

A. 40

Step-by-step explanation:

75 ÷ 1.5 = 50 = original number

80% of 50 = 50 × 0.8 = 40

write 16.76 correct to the nearest whole number​

Answers

16.76 rounds off to 17
After the dot if it’s 1-4 then they it would’ve been 15
5-9 is 17

Answer:

17

Step-by-step explanation:

because they are both above 5 so add 1

At a coffee shop, the first 100 customers'
orders were as follows.
Medium Large
Small
Hot
5
48
22
Cold
8
12
5
What is the probability that a customer ordered
a small given that he or she ordered a hot
drink?
Rounded to the nearest percent, [? ]%

Answers

Well formatted distribution table is attached below :

Answer:

7%

Step-by-step explanation:

The probability that a customer ordered a small Given that he or she ordered a hot drink ;

This is a conditional probability and will be represented as :

Let :

P(small drink) = P(S)

P(hot drink) = P(H)

Hence, the conditional probability is written as :

P(S|H) = P(SnH) / P(H) = 5 / (5+48+22) = 5/75 = 0.0666 = 0.0666 * 100% = 6.67%

solve the system of equation — 3х + бу = 9
5х + 7y = -49

Answers

Answer:

y = 64/3

x = -119/3

Step-by-step explanation:

3х + 6у = 9 => 5*3x+5*6у = 9*5 => 15x+30у=45 (1)

5х + 7y = -49 => 3*5x + 3*7y = -49*3 => 15x+21y=-147 (2)

(1)-(2) => 9y = 192 => y = 64/3

x = -119/3

The lengths of pregnancies are normally distributed with a mean of days and a standard deviation of days. a. Find the probability of a pregnancy lasting days or longer. b. If the length of pregnancy is in the lowest ​%, then the baby is premature. Find the length that separates premature babies from those who are not premature.

Answers

Answer:

a) The probability of a pregnancy lasting X days or longer is given by 1 subtracted by the p-value of [tex]Z = \frac{X - \mu}{\sigma}[/tex], in which [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.

b) We have to find X when Z has a p-value of [tex]\frac{a}{100}[/tex], and X is given by: [tex]X = \mu - Z\sigma[/tex], in which [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.

Step-by-step explanation:

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

In this question:

Mean [tex]\mu[/tex], standard deviation [tex]\sigma[/tex]

a. Find the probability of a pregnancy lasting X days or longer.

The probability of a pregnancy lasting X days or longer is given by 1 subtracted by the p-value of [tex]Z = \frac{X - \mu}{\sigma}[/tex], in which [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.

b. If the length of pregnancy is in the lowest a​%, then the baby is premature. Find the length that separates premature babies from those who are not premature.

We have to find X when Z has a p-value of [tex]\frac{a}{100}[/tex], and X is given by: [tex]X = \mu - Z\sigma[/tex], in which [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.

Solve by graphing. Round each answer to the nearest tenth.

6x2 = −19x − 15
a: −2, 1.7
b: −1.7, −1.5
c: −1.5, 1.5
d: −1.5, 1.7

Answers

9514 1404 393

Answer:

  b:  -1.7, -1.5

Step-by-step explanation:

The graph is shown below. We have annotated the x-intercepts for the equivalent equation ...

  6x^2 +19x +15 = 0

the complement of guessing 5 correct answers on a 5 question true or false examination is ​
​​​

Answers

Answer:

Guessing at least one incorrect answer

Step-by-step explanation:

The complement of guessing 5 correct answers on a 5-question true/false exam is-

Guessing at least one incorrect answer because, when 1 or more questions are incorrectly guessed, the event of 5 correct answers can not occur.

1.A multiple choice exam has five possible answers per question. Only one of those five answers is the correct answer. A student, who did not prepare for the test,answers the exam randomly and in order,starting from the first question. a.What is the probability that the first question he answered correctly is the second question

Answers

Answer:

Step-by-step explanation:

P(answers correctly)=1/5

P(answers incorrectly)=1-1/5=4/5

P( answers correctly second question)=4/5 ×1/5=4/25

solve the inequality (3-z)/(z+1) ≥ 1 please show the steps and the interval notation. thank you!​

Answers

Answer:

The solution (- infinity , 1].

Step-by-step explanation:

[tex]\frac{3 - z}{z + 1}\geq 1\\\\3 - z \geq z +1\\\\3-1 \geq2 z\\\\2 \geq 2 z\\\\z\leq 1[/tex]

So, the solution (- infinity , 1]

answer please don't skip plz answer

What is the value of x^2

-2xy+y^2

if x-y = 4 ?

please answer ​

Answers

Answer:

16

Step-by-step explanation:

[tex]x^2 - 2xy + y^2 = (x -y)^2 \\[/tex]

                   [tex]= 4^2 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ given : x - y= 4 \ ]\\\\= 16[/tex]

The value of x^2-2xy+y^2

will be 16 .

Explanation is in the attachment .

hope it is helpful to you ☺️

Question 1
Assume that a procedure yields a binomial distribution.
n = 48 p = 0.44. Find the mean.

Answers

Answer:

The mean is 21.12.

Step-by-step explanation:

Binomial probability distribution

Probability of exactly x successes on n repeated trials, with p probability.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

In this question:

[tex]n = 48, p = 0.44[/tex]

Mean:

[tex]E(X) = np = 48(0.44) = 21.12[/tex]

The mean is 21.12.

Matthew participates in a study that is looking at how confident students at SUNY Albany are. The mean score on the scale is 50. The distribution has a standard deviation of 10 and is normally distributed. Matthew scores a 65. What percentage of people could be expected to score the same as Matthew or higher on this scale

Answers

Answer:

The percentage of people that could be expected to score the same as Matthew or higher on this scale is:

= 93.3%.

Step-by-step explanation:

a) Data and Calculations:

Mean score on the scale, μ = 50

Distribution's standard deviation, σ = 10

Matthew scores, x = 65

Calculating the Z-score:

Z-score = (x – μ) / σ

= (65-50)/10

= 1.5

The probability based on a Z-score of 1.5 is 0.93319

Therefore, the percentage of people that could be expected to score the same as Matthew or higher on this scale is 93.3%.

A. 1
B. 9
C. 10
D.1/9

Answers

Answer:

B. 9

Step-by-step explanation:

When the line runs( x variation) by 1 , it rises (y variation) by 9

And since unit rate is calculated by Rise/Run, the unit rate is 9/1 or 9

If my answer is incorrect, pls correct me!

If you like my answer and explanation, mark me as brainliest!

-Chetan K

T=3 and t=5 to determine if the expression 4(t+3) and 4 t+12 are equivalent

Answers

No they’re not equivalent because 4(t+12) =68 and 4t+12=32

98 POINTS!!!
Respond to this question to demonstrate your understanding of the topic/content. Be sure to provide adequate and relevant details learned in the module to support your response. Pay close attention to organizing your response so it makes sense and uses correct grammar. Your response should be at least 5-7 sentences at a minimum.
Question: Consider the graph of f(x) = 5x + 1. Explain how to find the average rate of change between x = 0 and x = 4. What is the average rate of change?

Answers

Answer:

The average rate of change is 5.

Step-by-step explanation:

First plug in the x values.

y=5x+1

=(0)5+1

=1

y=5x+1

=(4)5+1

=21

Average rate of change = the change in the output divided by the change in the input.

Output change: 21-1=20

Input change: 4-0=4

20/4=5

20/4 = 5 sorry if its wrong

Seth and Ted can paint a room in 5 hours if they work together. If Ted were to work by himself, it would take him 2 hours longer than it would take Seth working by himself. How long would it take Seth to paint the room by himself if Ted calls in sick?

Answers

Answer:

9 hours

Step-by-step explanation:

Let

x = number of hours it would take Seth to work by himself

He would paint 1/x in 1 hour

x + 2 = number of hours it would take Ted to work by himself

He would paint 1/(x + 2) in 1 hour

Seth and Ted = 5 hours

They would paint 1/5 in 1 hour

The equation is this:

1/x + 1/(x + 2) = 1/5

(x + 2)+x/x(x+2) = 1/5

x+2+x / x(x+2) = 1/5

2x + 2 / x(x+2) = 1/5

2x + 2 = x(x + 2)1/5

2x + 2 = (x² + 2x)1/5

5(2x + 2) = x² + 2x

10x + 10 = x² + 2x

x² + 2x - 10x - 10 = 0

x² - 8x - 10 = 0

x = -b ± √b² - 4ac/2a

= -(-8) ± √(-8)² - 4(1)(-10) / 2(1)

= 8 ± √64 - (-40) / 2

= 8 ± √64 + 40) / 2

= 8 ± √104 / 2

= 8 ± 2√26 / 2

= 8/2 ± 2√26/2

= 4 ± √26

= 4 ± 5.0990195135927

= 4 + 5.0990195135927 or 4 - 5.0990195135927

= 9.0990195135927 or -1.Answer:

Step-by-step explanation:

Let

x = number of hours it would take Seth to work by himself

He would paint 1/x in 1 hour

x + 2 = number of hours it would take Ted to work by himself

He would paint 1/(x + 2) in 1 hour

Seth and Ted = 5 hours

They would paint 1/5 in 1 hour

The equation is this:

1/x + 1/(x + 2) = 1/5

(x + 2)+x / x(x+2) = 1/5

x+2+x / x(x+2) = 1/5

2x + 2 / x(x+2) = 1/5

Cross product

2x + 2 = x(x + 2)1/5

2x + 2 = (x² + 2x)1/5

Cross product

5(2x + 2) = x² + 2x

10x + 10 = x² + 2x

x² + 2x - 10x - 10 = 0

x² - 8x - 10 = 0

x = -b ± √b² - 4ac/2a

= -(-8) ± √(-8)² - 4(1)(-10) / 2(1)

= 8 ± √64 - (-40) / 2

= 8 ± √64 + 40) / 2

= 8 ± √104 / 2

= 8 ± 2√26 / 2

= 8/2 ± 2√26/2

= 4 ± √26

= 4 ± 5.0990195135927

= 4 + 5.0990195135927 or 4 - 5.0990195135927

= 9.0990195135927 or -1.0990195135927

Approximately,

x = 9 hours or -1 hour

It can't take Seth negative hours to work

Therefore,

x = number of hours it would take Seth to work by himself = 9 hours

What does y equal in the solution of the system of equations below? 5y-3x-4z=22 2z-2x=-6 2z+3x=-6

Answers

9514 1404 393

Answer:

  y = 2

Step-by-step explanation:

Subtracting the second equation from the third gives ...

  (2z +3x) -(2z -2x) = (-6) -(-6)

  5x = 0

  x = 0

Using this in the third equation, we have ...

  2z +0 = -6

  z = -3

And substituting these values into the first equation, we have ...

  5y -3(0) -4(-3) = 22

  5y = 10 . . . . . subtract 12

  y = 2

__

The solution to the system is (x, y, z) = (0, 2, -3).

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Nolan and Sadie have a contract with Green Goddess Lawn Service to mow the lawn and take care of the landscape. They pay $200 per month for this service. After two weeks had gone by with no service, Nolan called the company only to find out that the owner and the crew had decided to take a vacation and would not be back to do the landscaping for another two weeks. Green Goddess A) has discharged its obligation to Nolan and Sadie. B) is liable for specific performance. C) will likely have to pay Nolan and Sadie damages if they decide to sue them. D) will not likely have to pay Nolan and Sadie damages if they decide to sue them. Outline five things that are likely to happen in a Christian wedding service. In MQN, ma.Solve for x. Show all work.b. Find the measure of definition of public administration The phone rings in the next room and the assistant answers it. She tells the caller, "Yes, sir, he is here." After a moment she adds: "He has been here for about five or ten minutes, sir." 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The two-bottle system, supplied by Jay, gave Washington the secure form of writing that he wanted.Which statement best expresses the central idea of the excerpt?James Jay was a spy for the Americans and had knowledge of chemistry.James Jays system required two chemicals for writing and reading invisible ink messages.James Jay believed secret messages that became visible because of heat were not secure.James Jays invisible ink system allowed Washington to read secret messages. A boy spent 20% of his money on books and 20% of the remainder on food.If he had $2000 left, how much money did he have at first?