Suppose scores on exams in statistics are normally distributed with an unknown population mean and a population standard deviation of three points. A random sample of 36 scores is taken and gives a sample mean of 68. Find a 85 % confidence interval estimate for the population mean exam score. Explain what the confidence interval means
Answers
this the answer of queastions
Step-by-step explanation:
67.18,68.82
Let mu be the true population mean of statistics exam scores. We have a large random samples of n=36 scores with a sample mean of 68.we know that the population standard deviation is sigma=3.A pivotal quantity is 3^sqrt(36)=(3/6)=68(1/2) which is approximately normally distributed. Therefore the 85%confidence interval is 68-(1/2)(1.6449), 68+(1/2)(1.6449) i.e (67.18,68.82)
Related Questions
Rules for multiplying exponents
Answers
Answer and Step-by-step explanation:
When multiplying exponents:
- Product of Powers: When the base of the exponents are the same, and the bases are being multiplied to each other, the exponents are added together.
Example: [tex]a^x + a^y = a^{x+y}[/tex]
- Different bases Same Exponents: When the bases of the exponents are different, but the exponents are the same, the bases multiply together (within a parenthesis) with the exponent on the parenthesis.
Example: [tex]a^x*b^x = (a*b)^x[/tex]
- Quotient of Powers: When the base of the exponents are the same, and they are being divided by each other, the exponents will subtract from each other.
Example: [tex]\frac{a^x}{a^y}= a^{x-y}[/tex]
- Power of a Power: When a base has an exponent, and that entire term has and exponent, the exponents multiply together.
Example: [tex](a^x)^y = a^{x*y}[/tex]
- Power of a Product: The opposite of Different bases Same Exponents. Distribute the exponent onto the different bases.
Example: [tex](ab)^x = a^x*b^x[/tex]
- Power of a Quotient: The opposite of Quotient of Powers. Distribute the exponent to the dividing bases.
Example: [tex](\frac{a}{b} )^x = \frac{a^x}{b^x}[/tex]
- Zero Power: Any number raised to the 0 power equals 1.
Example: [tex]a^0 = 1\\999999^0=1[/tex]
- Negative Exponent: Any number raised by a negative number goes to the denominator of a fraction (if not already in the denominator), and vise versa (goes to the numerator if not already in the numerator).
Example: [tex]a^-2 = \frac{1}{a^2} \\\\\frac{1}{b^-3} = b^3[/tex]
- Power of One: Any number raised to the power of 1 is the same number.
Example: [tex]a^1 = a\\\\999^1 = 999[/tex]
I hope this helps!
#teamtrees #PAW (Plant And Water)
if 12 +2 =2 orderly what is 6 +3 orderly
Answers
Answer:
3
Step-by-step explanation:
Please Mark me brainliest
Answer:
aren't one of the numbers in the equations supposed to be negative?
Test scores are normally distributed with a mean of 68 and a standard deviation of 12. Find the z – score for a grade of 74. Round your answer to two numbers after the decimal.
Answers
Answer:
gang nem
Step-by-step explanation:
Cho A=( căn x -4x /1-4x -1) : (1+2x/1-4x -2căn x/ 2căn x -1 -1)
Answers
Answer:
0.85714285714286 x 100 = 85.7143%.
Step-by-step explanation:
what is a cell and why it is necessary
Answers
Cells are the basic building blocks of living things. The human body is composed of trillions of cells, all with their own specialised function. Cells are the basic structures of all living organisms.
IMPORTANCECells provide structure for the body, take in nutrients from food and carry out important functions.
I HOPE THIS WILL HELP YOU IF NOT THEN SORRYHAVE A GREAT DAY :)
A physical trainer decides to collect data to see if people are actually weight changing weight during the shelter in place. He believes there will not be a meaningful change in weight due to the shelter in place order. He randomly chooses a sample of 30 of his clients. From each client, he records their weight before the shelter in place order, and again 10 days after the order. A summary of the data is below.
The trainer claims, "on average, there is no difference in my clients' weights before and after the shelter in place order." Select the pair of hypotheses that are appropriate for testing this claim.
H0: µd = 0
H1: µd < 0 (claim)
H0: µd = 0 (claim)
H1: µd ≠ 0
H0: µd ≠ 0 (claim)
H1: µd = 0
H0: µd = 0 (claim)
H1: µd > 0
H0: µd = 0
H1: µd > 0 (claim)
H0: µd = 0
H1: µd ≠ 0 (claim)
H0: µd = 0 (claim)
H1: µd < 0
H0: µd ≠ 0
H1: µd = 0 (claim)
b) Select the choice that best describes the nature and direction of a hypothesis test for this claim.
This is a right-tail t-test for µd.
This is a right-tail z-test for µd.
This is a two-tail t-test for µd.
This is a two-tail z-test for µd.
This is a left-tail t-test for µd.
This is a left-tail z-test for µd.
c) Find the standardized test statistic for this hypothesis test. Round your answer to 2 decimal places.
d) Find the P-value for this hypothesis test. Round your answer to 4 decimal places.
e) Using your previous calculations, select the correct decision for this hypothesis test.
Fail to reject the alternative hypothesis.
Reject the alternative hypothesis.
Fail to reject the claim.
Reject the claim.
Fail to reject the null hypothesis.
Reject the null hypothesis.
f) Consider the following statements related to the trainer's claim. Interpret your decision in the context of the problem (ignoring the claim) and interpret them in the context of the claim.
Answers
Answer:
H0: µd = 0 (claim)
H1: µd ≠ 0
This is a two-tail t-test for µd
Step-by-step explanation:
This is a paired (dependent) sample test, with its hypothesis is written as :
H0: µd = 0
H1: µd ≠ 0
From the equality sign used in the hypothesis declaration, a not equal to ≠ sign in the alternative hypothesis is used for a two tailed t test
The data isn't attached, however bce the test statistic cannot be obtained. However, the test statistic formular for a paired sample is given as :
T = dbar / (Sd/√n)
dbar = mean of the difference ; Sd = standard deviation of the difference.
guys pls tell me this answer as soon as possible
Answers
que es un cuadrilatero
PLEASE HELP!! URGENT
Answers
Answer:
y=105
Step-by-step explanation:
82+75+x=180
157+x=180
x=23
82+23=y
105=y
[tex] \frac{3x - 2}{7} - \frac{5x - 8}{4} = \frac{1}{14} [/tex]
Answers
Answer:
[tex]x=2[/tex]
Step-by-step explanation:
[tex]\frac{3x-2}{7}-\frac{5x-8}{4}=\frac{1}{14}[/tex]
In order to factor an integer, we need to divide it by the ascending sequence of primes 2, 3, 5.
The number of times that each prime divides the original integer becomes its exponent in the final result.
In here, Prime number 2 to the power of 2 equals 4.
[tex]\frac{3x-2}{7}-\frac{5x-8}{2^{2} }=\frac{1}{14}[/tex]
First, We need to add fractions-
Rule:-
[tex]\frac{A}{B} +\frac{C}{D} =\frac{\frac{LCD}{B}+\frac{LCD}{D}C }{LCD}[/tex]
LCD = [tex]7 \cdot 2^{2}[/tex]
[tex]\frac{4(3x-2)+7(-(5x-8))}{7*2^{2} } =\frac{1}{14}[/tex]
[tex]x=2[/tex]
OAmalOHopeO
1/6+4/18 in simplest form
Answers
Answer:
7/18
Step-by-step explanation:
1/6 x 3 = 3/18
3/18 + 4/18 = 7/18
Answer:
7/18
Step-by-step explanation:
Make the denominators the same!
You can turn 1/6 into 3/18 by multiplying the numerator and denominator by 3. Then you add the numerators of 3/18 and 4/18 together to get 7/18.
It can't be simplified any further :)
Find the value of x. Round to the nearest tenth.
Answers
Answer:
1.6 ft
Step-by-step explanation:
If you use the Pythagorean Theorem to solve for x, you get:
[tex]x=\sqrt{2.1^2-1.4^2}[/tex]
[tex]x=\sqrt{2.45} = 1.56524758425[/tex]
Rounded to the nearest tenth, the answer is 1.6
a word problem on proportions using a unit rate
Lashonda made $273 for 13 hours of work.
At the same rate, how many hours would she have to work to make $231?
hours
Х
?
Answers
eleven hours - 11 hours
Step 1: 273/13 = 21
So, x equals 21
Step 2: 231/21 = 11
According to the graph of the rational function y equals 4 over the quantity x squared minus 4 end quantity which of the following statements is/are true? The function is even. The function is increasing for all values in the domain. There is a horizontal asymptote along the x-axis. I only I and II only I and III only I, II, and III
Answers
Using function concepts, it is found that the correct options are:
I and III only
--------------------------------
The function is:
[tex]y = \frac{4}{x^2 - 4}[/tex]
--------------------------------
Statement 1:
A function is even if: [tex]f(x) = f(-x)[/tex]
We have that:
[tex]f(x) = \frac{4}{x^2 - 4}[/tex]
[tex]f(-x) = \frac{4}{(-x)^2 - 4} = \frac{4}{x^2 - 4} = f(x)[/tex]
Since [tex]f(x) = f(-x)[/tex], the function is even, and the statement is true.
--------------------------------
Statement 2:
The function increases when: [tex]f^{\prime}(x) > 0[/tex]
The derivative is:
[tex]f^{\prime}(x) = \frac{-8x}{(x^2-4)^2}[/tex]
The denominator is always positive, but the numerator can be both positive/negative, which means that when the numerator is negative(x > 0), the derivative will be negative, thus the function will decrease and the statement is false.
--------------------------------
Statement 3:
A horizontal asymptote is given by:
[tex]y = \lim_{x \rightarrow \infty} f(x)[/tex]
In this question:
[tex]y = \lim_{x \rightarrow \infty} \frac{4}{x^2 - 4} = \frac{4}{\infty - 4} = \frac{4}{\infty} = 0[/tex]
y = 0 is the x-axis, thus, the statement is true, and the correct option is:
I and III only
A similar problem is given at https://brainly.com/question/23535769
Answer:
I and III
Step-by-step explanation:
please help solve for y!
Answers
As both angles are supplementary
[tex]\\ \Large\sf\longmapsto 3x+(2x+3y)=180°[/tex]
[tex]\\ \Large\sf\longmapsto 3x+2x+3y=180[/tex]
[tex]\\ \Large\sf\longmapsto 5x+3y=180[/tex]
[tex]\\ \Large\sf\longmapsto 3y=180-5x[/tex]
[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5x}{3}[/tex]
And
[tex]\\ \Large\sf\longmapsto 3x=90[/tex]
[tex]\\ \Large\sf\longmapsto x=\dfrac{90}{3}[/tex]
[tex]\\ \Large\sf\longmapsto x=30[/tex]
Now
Putting value[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5x}{3}[/tex]
[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5(30)}{3}[/tex]
[tex]\\ \Large\sf\longmapsto y=\dfrac{180-150}{3}[/tex]
[tex]\\ \Large\sf\longmapsto y=\dfrac{30}{3}[/tex]
[tex]\\ \Large\sf\longmapsto y=10[/tex]
Jared works at a clothing store and is listening to a customer complain about a shirt he purchased that's damaged. Which behavior can Jared exhibit to show good communication skills with the customer? O a) Stopping the customer to quickly explain the store's return policy b) Repeating back what he has heard once the customer is done speaking Od Asking the customer how the shirt was damaged O d) Promising the customer a full refund even though it's against policy
Answers
Answer:
C
Step-by-step explanation:
in my point of view, my choice is C (asking the customer how the shirt was damaged) because when he finds out the reason why the shirt was damaged, he will explain whether or not that fault is in the store's return policy
another reason:
A) stopping the customers when they are talking, it's impolite behavior and i ensure that that customer will feel disatified.
B) i guess that customer doesnt waste of time because it
D) a full refund without finding the reason, i dont think it's a good idea
look at the image below
Answers
Answer:
SA = 153.9m^2
Step-by-step explanation:
SA = 4[tex]\pi[/tex][tex]r^{2}[/tex]
r = 3.5
SA = 4[tex]\pi[/tex][tex](3.5)^{2}[/tex]
SA = 4[tex]\pi[/tex](12.25)
SA = 49[tex]\pi[/tex]
SA = 153.9m^2
Find the distance between the points (-4, -2) and (-8, 6)
Answers
Answer:
distance=√[(x2-x1)²+(y2-y1)²]
√[{6-(-2)}²+ (-8-(-4))²]
√(64+16)
√[100]
10
Points given
(-4,-2)(-8,-6)Distance:-
[tex]\\ \sf \longmapsto \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
[tex]\\ \sf \longmapsto \sqrt{(-8+4)^2+(6+2)^2}[/tex]
[tex]\\ \sf \longmapsto \sqrt{(-4)^2+(8)^2}[/tex]
[tex]\\ \sf \longmapsto \sqrt{64+16}[/tex]
[tex]\\ \sf \longmapsto \sqrt{80}[/tex]
[tex]\\ \sf \longmapsto 8.4[/tex]
help please! I need the answer quickly! thank you!
Answers
Answer:
B) 1 unit to the left
Step-by-step explanation:
Find two numbers nearest to 8888888 which are exactly divisible by 2915 explain step by step
Answers
Step-by-step explanation: 88,87,835 =2915*3049 , 8890750 = 2915*3050.
Simplify the given expression.
Answers
Answer:
8x-21
----------------------
(2x-7)(2x+7)
Step-by-step explanation:
7 4
----------- + ------------
4x^2 -49 2x+7
Factor ( notice that it is the difference of squares)
7 4
----------- + ------------
(2x)^2 - 7^2 2x+7
7 4
----------- + ------------
(2x-7)(2x+7) 2x+7
Get a common denominator
7 4(2x-7)
----------- + ------------
(2x-7)(2x+7) (2x-7)(2x+7)
Combine
7 +4(2x-7)
----------------------
(2x-7)(2x+7)
7 +8x-28
----------------------
(2x-7)(2x+7)
8x-21
----------------------
(2x-7)(2x+7)
Answer:
(8x - 21) / (2x + 7)(2x - 7)
Step-by-step explanation:
7 / (4x^2 - 49)+ 4 / (2x + 7)
= 7 / (2x + 7)(2x - 7) + 4 / (2x + 7)
LCM = (2x + 7)(2x - 7) so we have
(7 + 4(2x - 7) / (2x + 7)(2x - 7)
= (8x - 21) / (2x + 7)(2x - 7).
A sample of 375 college students were asked whether they prefer chocolate or vanilla ice cream. 210 of those surveyed said that they prefer vanilla ice cream. Calculate the sample proportion of students who prefer vanilla ice cream.
Answers
Answer:
The sample proportion of students who prefer vanilla ice cream is 0.56.
Step-by-step explanation:
Sample proportion of students who prefer vanilla ice cream:
Sample of 375 students.
Of those, 210 said they prefer vanilla ice cream.
The proportion is:
[tex]p = \frac{210}{375} = 0.56[/tex]
The sample proportion of students who prefer vanilla ice cream is 0.56.
Find the value of x round to the nearest tenth.
Answers
9514 1404 393
Answer:
117.9°
Step-by-step explanation:
Solving the Law of Cosines equation for C, we get ...
C = arccos((a² +b² -c²)/(2ab))
Filling in the values from the figure, we find the angle X to be ...
X = arccos((y² +z² -x²)/(2yz)) = arccos((55² +50² -90²)/(2·55·50))
X = arccos(-2575/5500) ≈ 117.9°
in triangle JKL, angle JKL is a right angle, line KM is an altitude, JL=20, ML=4. Find KM
Answers
9514 1404 393
Answer:
KM = 8
Step-by-step explanation:
The ratio of long side to short side is the same for all of the triangles in this geometry:
KM/ML = JM/KM
KM² = ML·JM = 4(20-4) = 64
KM = √64 = 8
The length of KM is 8 units.
How many
Assume that the mean hecaht of soldiers is 166cm
with a standard deration of 8. cm.
soldeers in a regiment of 1000 would you expect to
be over 177 cm tall.
Answers
Answer:
85
Step-by-step explanation:
Given that :
Mean height , μ = 166
Standard deviation, σ = 8
Sample size, n = 1000
Using the Zscore formula :
Zscore = (x - μ) / σ
x = 177
Z = (177 - 166) / 8
Z = 1.375
P(Z > 1.375) = 0.084566(Area to the right of Z)
P(Z > 1.375) * n
0.084566 * 1000 = 84.566 = 85 soldiers
How many unit cubes are on each layer of the cube?
6
3
12
9
Answers
Answer:
6
Step-by-step explanation:
Remember: Each layer has 6 cubes. Step 3 Count the cubes. cubes Multiply the base and the height to check your answer. So, the volume of Jorge's rectangular prism is cubic centimeters. if wrong very sorry
Answer:
9
Step-by-step explanation:
took the test
Tom and Jerry had a race. Tom started at 0200 running at 4.5km per hour. Jerry started
later at 6:30am running at 6.5km per hour. After five hours, who was ahead, and by how
much (answer in kilometres)
Answers
Answer:
Tom, 10.25
Step-by-step explanation:
Distance covered by Tom=4.5*(4 1/2+5)=81/4=42.75km
Distance covered by Jerry=6.5*(5)=32.5km
Tom is ahead from Jerry by 10.25km
Find two consecutive even numbers whose sum is 758.
Answers
Answer:
378 and 380
Step-by-step explanation:
The two even consecutive numbers that add up to 758 are going to be very close to half of 758. This is because two half of 758 are going to be the most similar addends of 758. This is important because the answers will be consecutive and therefore, must also be very similar. To solve, first, divide 758 by 2. This is 379, which is not an even number. So, to find the needed addends subtract and add 1 to 379. Both of these will be even and consecutive. These two numbers are 378 and 380. Then, to check you, can add them and see that they do sum 758.
Answer:
Step-by-step explanation:
Let the first number = x
Let the second number = x + 2
x + x + 2 = 758 Collect like terms
2x + 2 = 758 Subtract 2
2x = 758 - 2 Combine
2x = 756 Divide by 2
2x/2 = 756/2
x = 378
The first number is 378
The second number 380
If your teacher is really fussy, you can do it this way.
Let the first number = 2x
Let the second number = 2x + 2
The reason for this is to guarantee that both numbers were even to start with.
2x + 2x+2 = 758 Combine like terms
4x + 2 = 758 Subtract 2
4x = 756 Divide by 4
x = 756/4
x = 189
Therefore 2x = 378
2x + 2 = 380 Just as before.
Turn 43 1/23 into an improper fraction
Answers
Answer:
990/23
Step-by-step explanation:
Step 1
Multiply the denominator by the whole number
23 × 43 = 989
Step 2
Add the answer from Step 1 to the numerator
989 + 1 = 990
Step 3
Write answer from Step 2 over the denominator
990/23
I hope this answer helps you out! Brainliest would be appreciated.
Plzzz I’m giving a away 25 points
Answers
Answer:
sin ß = opposite / hypotenuse
sin45° = x / 4√2
Cross multiply
x = sin 45° × 4√2
x = √2/2 × 4√2
x = 4 × √2 ×√2 / 2
x = 4 × 2 / 2
x = 8 / 2
x = 4
When a sample has an even number of observations, the median is the
Group of answer choices
observation in the center of the data array
average of the two observations in the center of the data array
value of the most frequent observation
Answers
Answer:
average of the two observations in the center of the data array
Step-by-step explanation:
When there is an odd number, we use the middle
Example
1,5,9
The median is 5
When there is an even number
1,3,5,7
The middle is between the 3 and 5 so we average the middle number
(3+5)/2 = 4
Answer:
the answer is => observation in the center of the data array
Step-by-step explanation:
[tex]\sf{}[/tex]
