You want to create an 80% confidence interval for the average age of people who attend U of O football games. You take a sample of 100 attendees and find the average age to be 43.7 years old with a standard deviation of 7 years. Find the value of t* for this confidence interval. Do not round your answer. Write your answer in decimal form, not as a fraction or percent.

Answers

Answer 1

Answer:

Answer:

80% confidence interval for the average age of people who attend U of O football games is [42.795 , 44.604].

Step-by-step explanation:

We are given that a sample of 100 attendees and find the average age to be 43.7 years old with a standard deviation of 7 years.

So, the pivotal quantity for 80% confidence interval for the population average start up cost is given by;

P.Q. = $(\bar X - \mu)/((s)/(√(n) ) )$ ~ $t_n_-_1$

where, $\mu$ = sample average age = 43.7 years old

$\sigma$ = sample standard deviation = 7 years

n = sample of attendees = 100

$\mu$ = population average age of people

So, 80% confidence interval for the average age of people, $\mu$ is ;

P(-1.2915 < $t_9_9$ < 1.2915) = 0.80

P(-1.2915 < $(\bar X - \mu)/((s)/(√(n) ) )$ < 1.2915) = 0.80

P( $-1.2915 * {(s)/(√(n) )$ < ${\bar X - \mu}$ < $1.2915 * {(s)/(√(n) )$ ) = 0.80

P( $\bar X -1.2915 * {(s)/(√(n) )$ < $\mu$ < $\bar X +1.2915 * {(s)/(√(n) )$ ) = 0.80

80% confidence interval for $\mu$ = [ $\bar X -1.2915 * {(s)/(√(n) )$ , $\bar X +1.2915 * {(s)/(√(n) )$ ]

= [ $43.7 -1.2915 * {(7)/(√(100) )$ , $43.7 +1.2915 * {(7)/(√(100) )$ ]

= [42.795 , 44.604]

Therefore, 80% confidence interval for the population average age of people who attend U of O football games is [42.795 , 44.604].

WHAT IS A POLYNOMIAL

In mathematics, a polynomial is an expression consisting of indeterminates (also called variables) and coefficients, that involves only the operations of addition, subtraction, multiplication, and non-negative integer exponentiation of variables.

How to Solve?

Given , we need to add $2x^2-8x-6$ and $9x^2-8$ .

So, we can write it as :

$2x^2 -8x-6+9x^2-8$

Writing like terms together:

$= 2x^2+9x^2-8x-6-8$

$=11x^2-8x-14$

Hence , the answer is $11x^2-8x-14$ .

Learn more about Algebraic expressions :

brainly.com/question/395066

#SPJ2

Answer:f

(x)=x, g(x)=x3−1f(x)=x4+x3−11x2−5x+30, g(x)=2x−2f(x)=x2, g(x)=7x−1

in short ways the answer is 7x−1

Solve F(x) for the given domain.F(x)= x2 + 3x-2
F(-1) =
Jutaານເພະາ
a. -4
b. -6
C. 2.

Answers

Answer:

A. -4

Step-by-step explanation:

F(-1) means we must plug the number "-1" in for each x.

F(x) = x^2 + 3x - 2

F(-1) = (-1)^2 + 3(-1) - 2

= 1 - 3 - 2

= -4

Let X1, X2, and X3 represent the times necessary to perform three successive repair tasks at a service facility. Suppose they are normal random variables with means of 50 minutes, 60 minutes, and 40 minutes, respectively. The standard deviations are 15 minutes, 20 minutes, and 10 minutes, respectively. a Suppose X1, X2, and X3 are independent. All three repairs must be completed on a given object. What is the mean and variance of the total repair time for this object.

Answers

Answer:

The mean of the total repair time is 150 minutes.

The variance of the total repair time is 725 minutes^2.

Step-by-step explanation:

To solve this problem, we have to use the properties of the mean and the variance. Our random variable is the sum of 3 normal variables.

In the case, for the mean, we have that the mean of the sum of 3 normal variables is equal to the sum of the mean of the 3 variables:

$y=x_1+x_2+x_3 \n\nE(y)=E(x_1+x_2+x_3)=E(x_1)+E(x_2)+E(x_3)\n\nE(y)=50+60+40=150$

For the variance, we apply the property for the sum of independent variables (the correlation between the variables is 0):

$V(y)=V(x_1)+V(x_2)+V(x_3)\n\nV(y)=s_1^2+s_2^2+s_3^2\n\nV(y)=15^2+20^2+10^2\n\nV(y)=225+400+100\n\nV(y)=725$

Hi I need help with the one that is circle thank you

Answers

Answer:

B1: +6 (to get to plus six you would have to pass negative one so really it's seven)

B2: they are the same distance

B3: -7

B4: +7

<3 have a good day :)

Step-by-step explanation:

Answer:

hope this helped! Can I get brainliest? :)) please?

Step-by-step explanation:

1. +6 is the answer because it is 8 units away from -2

2. both are the same distance from -2

3. -7 is the answer because it is 5 units away from -2

4. +7 is the answer because it is 9 units away from -2

Hello can you please help me posted picture of question

Answers

The discriminant help us to identify the nature of the roots.

If Disc > 0, the function has two distinct roots
If Disc = 0, the function has repeated roots
If Disc < 0, the function has complex roots

The turning away of the function indicates a repeated root at that point.
Thus, the given quadratic equation has a repeated root at x = 2. So the discriminant of the function is zero.

Therefore, the correct answer is option B

As a promotional offer, a new gym is offering a 30% discount to those who sign up in the first month. Patty and her 2 siblings take advantage of the offer and sign up for a total amount of €210. What were the total savings mode? Work out the average savings per person