Answer:
.
Step-by-step explanation:
A civil engineer is analyzing the compressive strength of concrete. Compressive strength is normally distributed with A random sample of 12 sample specimens has a mean compressive strength of psi. Round your answers to 1 decimal place. (a) Calculate the 95% two-sided confidence interval on the true mean compressive strength of concrete. Enter your answer; 95% confidence interval, lower bound Enter your answer; 95% confidence interval, upper bound (b) Calculate the 99% two-sided confidence interval on the true mean compressive strength of concrete.
Answer:
95%: (3278.354 ; 3270.083)
99% : (3221.646 ; 3278.354)
Step-by-step explanation:
Given :
Sample size, n = 12
Mean, xbar = 3250
Sample standard deviation = √1000
The 95% confidence interval :
Mean ± Margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 0.05, df=12-1 = 11 ;
Tcritical at 95% = 2.20
Hence,
Margin of Error = (2.20 * √1000/√12) = 20.083
Confidence interval : 3250 ± 20.083
Lower boundary = 3250 - 20.083 = 3229.917
Upper boundary = 3250 + 20.083 = 3270.083
2.)
The 99% confidence interval :
Mean ± Margin of error
Margin of Error = Tcritical * s/√n
Tcritical at 0.01, df=12-1 = 11 ;
Tcritical at 99% = 3.106
Hence,
Margin of Error = (3.106 * √1000/√12) = 28.354
Confidence interval : 3250 ± 28.354
Lower boundary = 3250 - 28.354 = 3221.646
Upper boundary = 3250 + 28.354 = 3278.354
Which statements below represent the situation? Select three options.
Answer:
where is the statement
Step-by-step explanation:
its incomplete po
What is an amount between $2 and $10?
Answer:
6
Step-by-step explanation:
Please Help
Solve 3(x+2)-4x=8
Hello!
3(x + 2) - 4x = 8 <=>
<=> 3x + 6 - 4x = 8 <=>
<=> -x + 6 = 8 <=>
<=> -x = 8 - 6 <=>
<=> -x = 2 <=>
<=> x = -2
Good luck! :)
An initial deposit of $212 is placed in
a bank account and left to grow, with
interest compounded continuously.
what will it be after 6 years?
Round your answer to the nearest dollar.
Answer:
$224.932
Step-by-step explanation:
Note: The question is not complete
say the rate is 10%
Given data
Initial depostite= $212
TIme= 6years
rate= 10%
the expression for the compound interest is given as
A=P(1+r)^t
substitute
A=212(1+0.1)^6
A=212(1.01)^6
A=212*1.061
A= $224.932
Hence the final amount at the rate of 10% is $224.932
Which set of statements shows the correct steps to find 45 percent of 75?
A.
Write 45 percent as 9 ´ 5 percent, and write 5 percent as StartFraction 1 Over 20 EndFraction. Then, find StartFraction 1 Over 20 EndFraction of 75: 75 times StartFraction 1 Over 20 EndFraction = StartFraction 75 Over 20 EndFraction = 3.75. Multiply 3.75 by 9 to get 33.75. So, 45 percent of 75 is 33.75.
B.
Write 45 percent as 9 ´ 5 percent, and write 5 percent as One-half. Then, find One-half of 75: 75 times one-half = StartFraction 75 Over 2 EndFraction = 33.75. Multiply 33.75 by 9 to get 303.75. So, 45 percent of 75 is 303.75.
C.
Write 45 percent as StartFraction 1 Over 45 EndFraction. Then, find StartFraction 1 Over 45 EndFraction of 75: 75 times StartFraction 1 Over 45 EndFraction = StartFraction 75 Over 45 EndFraction = 1.67. So, 45 percent of 75 is 1.67.
D.
Write 45 percent as StartFraction 1 Over 4.5 EndFraction. Then, find StartFraction 1 Over 4.5 EndFraction of 75: 75 times StartFraction 1 Over 4.5 EndFraction = StartFraction 75 Over 4.5 EndFraction = 16.7. So, 45 percent of 75 is 16.7.
Pls the answer is
D
Thank you
You are welcome
Answer:
d
Step-by-step explanation:
im smart
Choose the correct answers for (a) the total installment price, (b) the carrying charges, and (c) the number of months needed to save money at the monthly rate to buy the item for its cash price.
A bunk bed with a cash price of $1,998, at $143 per month for 15 months
Answer:
$2,145 ; $147 ; 14 months
Step-by-step explanation:
Given that :
The cash price, that is, the amount that would be paid if customer is to pay the entire amount item is worth at once = $1998
Monthly payment = $143
Period = 15 months
The total installment price ; total amount paid on a monthly pay for 15 months :
(monthly payment * period)
($143 * 15)
= $2,145
The carrying charge :
Installment pay - Cash amount
$(2,145 - 1,998)
= $147
The number of month needed to save at Monthly rate to buy item at it's cash price :
Cash price / monthly payment
$1998 / $143
= 13.97
= 14 months
Write – 90 5/8 as a decimal number.
Answer:
-90.625
Step-by-step explanation:
Answer:
[tex]-90~5/8\\[/tex]
[tex]Decimal=-90.625[/tex]
-------------------------------
~HOPE IT HELP....~
~HAVE A GREAT DAY!!~
Determine the intercepts of the line
Y ——-,——-
X——-,——-
Answer:
(-8,0), (0,-6)
Step-by-step explanation:
You have to find the value of k
Answer:
115
Step-by-step explanation:
Suppose that you and a friend are playing cards and you decide to make a friendly wager. The bet is that you will draw two cards without replacement from a standard deck. If both cards are diamonds, your friend will pay you $296. Otherwise, you have to pay your friend $17.
What is the expected value of your bet?
Answer:
False because $296=$296
When randomly selecting adults, let M denote the event of randomly selecting a male and let B denote the event of randomly selecting someone with blue eyes. What does P(M|B) represent? Is P(M|B) the same as P(B|M)?
Answer:
See explanation
Step-by-step explanation:
Given
[tex]M \to[/tex] randomly selecting a male
[tex]B \to[/tex] randomly selecting someone with blue eyes
Solving (a): Interpret P(M|B)
The above implies conditional probability
The interpretation is: the probability of selecting a male provided that a person with blue eyes has been selected
Solving (b): is (a) the same as P(B|M)
No, they are not the same.
The interpretation of P(B|M) is: the probability of selecting a person with blue eyes provided that a male has been selected
William invested $12,000 in a bank account that pays 9 percent simple interest. His friend invested the same amount at another bank that pays 8 percent interest compounded quarterly. These two functions, where t is time in years, represent the value of the investments: f(t) = 12(1.02)4t g(t) = 12(1.09)t The functions are graphed, and the point of intersection lies between 0.5 and 1.2. Based on the table, approximately how long will it be until both investments have the same value? Value of t f(t) = 12(1.02)4t g(t) = 12(1.09)t 0.5 12.48 6.54 0.6 12.58 7.84 0.7 12.68 9.16 0.8 12.79 10.46 0.9 12.89 11.87 1.0 12.99 13.08 1.1 13.09 14.39 1.2 13.20 15.70 A. 0.9 year B. 1.0 year C. 1.1 years D. 1.2 years
===========================================================
Explanation:
We have these two functions
f(t) = 12(1.02)^(4t)g(t) = 12(1.09)twhich represent the amounts for his friend and William in that order. Strangely your teacher mentions William first, but then swaps the order when listing the exponential function as the first. This might be slightly confusing.
The table of values is shown below. We have t represent the number of years and t starts at 0.5. It increments by 0.1
The f(t) and g(t) columns represent the outputs for those mentioned values of t. For example, if t = 0.5 years (aka 6 months) then f(t) = 12.48 and that indicates his friend has 12,480 dollars in the account.
I've added a fourth column labeled |f - g| which represents the absolute value of the difference of the f and g columns. If f = g, then f-g = 0. The goal is to see if we get 0 in this column or try to get as close as possible. This occurs when we get 0.09 when t = 1.0
So we don't exactly get f(t) and g(t) perfectly equal, but they get very close when t = 1.0
It turns out that the more accurate solution is roughly t = 0.9925 which is close enough. I used a graphing calculator to find this approximate solution.
It takes about a year for the two accounts to have the same approximate amount of money.
Answer:
B
Step-by-step explanation:
Which is a correct statement about the description “two less than the quotient of a number cubed and sixteen, increased by eight” when n = 4?
Answer:
n = 4 is 10
hope it helps and have a good day
Simplify by expressing fractional exponents instead of radicals.
Which of the following consists of discrete data?
A. Number of suitcases on a plane.
B. Amount of rainfall.
C. Hair color.
D. Tree height.
Answer:
A
Step-by-step explanation:
Number of suitcases on a plane is discrete because you can only have an integer amount. You can't have a fraction of a suitcase on a plane.
A polygraph (lie detector) is an instrument used to determine if an individual is telling the truth. These tests are considered to be 90% reliable. In other words, if an individual lies, there is a 0.90 probability that the test will detect a lie. Let there also be a 0.045 probability that the test erroneously detects a lie even when the individual is actually telling the truth. Consider the null hypothesis, "the individual is telling the truth," to answer the following questions
a. What is the probability of a Type I error? (Round your answer to 3 decimal places.)
b. What is the probability of a Type II error? (Round your answer to 2 decimal places.
Answer:
A) P(Type I error) = 0.045
B) P(Type II) error = 0.1
Step-by-step explanation:
We are told that the reliability of the test is 90% reliable.
Also, we are told that the probability that the test erroneously detects a lie even when the individual is actually telling the truth is 0.045.
Thus;
A) To calculate the probability of type I error:
From statistics, in this question we can say that the probability of a type I error is the probability that the test will erroneously detect a lie even though the individual is actually telling the truth. Thus;
Probability of (type I error) = P(rejecting true null) = 0.045
B) For probability of type II error, it is defined as the error where we accept a null hypothesis that is false. We can say that it produces a false negative and the formula is;
P(Type II) error = 1 - reliability
Reliability in the question is 0.90
Thus;
P(Type II) error = 1 - 0.9
P(Type II) error = 0.1
please help i guess on a
Answer:
A = (2, 2)
B = (3, -1)
C = (-1, 0)
Step-by-step explanation:
To translate a point, you have to translate each individual point. At the bottom it shows <-2,3>, therefore you have to translate x 2 units to the left (because it's negative meaning the number is going away from 0, and 3 units to the right because 3 is a positive number.)
First Point A:
x: 4 - 2 = 2; y: -1 + 3 = 2
Second Point B:
x: 5 - 2 = 3; y: -4 + 3 = -1
Lastly, Point C:
x: 1 - 2 = -1, y: -3 + 3 = 0
I hope this helps!
If JKL - PNM. then M = L and the sides NP and
KJ are proportional.
True
Or
False???
Answer:
True
Step-by-step explanation:
In similarity triangles, corresponding angles are congruent and corresponding sides are in proportion.
Can I get the answer for those
Answer:
1) 5.64
2) 17.321
1) [tex]\frac{21}{28}[/tex]
2) [tex]\frac{16}{34}[/tex]
3) [tex]\frac{28}{35}[/tex]
4) [tex]\frac{32}{24}[/tex]
Step-by-step explanation:
SOH - CAH - TOA
Sin = [tex]\frac{O}{H}[/tex] Cos = [tex]\frac{A}{H}[/tex] Tan = [tex]\frac{O}{A}[/tex]
O = opposite, A = adjacent, H = hypotenuse
First two, use Pythagorean Theorem
If you want to calculate the angle on the last 4, use inverse of function and put in the ratio.
For example :
1) Tan Z = [tex]\frac{21}{28}[/tex]
[tex]Tan^{-1}[/tex] ( [tex]\frac{21}{28}[/tex])
Z = 36.9°
Identify the transformation that occurs to create the graph of g(x). g(x)=f(x)-7
Answer:
g(x) is obtained by shift the function f(x) down 7 units by subtracting 7 units from f(x).
Step-by-step explanation:
We are given that
[tex]g(x)=f(x)-7[/tex]
We have to identify the transformation that occurs to create the graph of g(x).
To identify the transformation that occurs to create the graph of g(x)
We will subtract the 7 from f(x).
Let f(x) be any function
[tex]g(x)=f(x)-k[/tex]
It means g(x) obtained by shift the function f(x) down k units by subtracting k units from f(x).
Therefore, g(x) is obtained by shift the function f(x) down 7 units by subtracting 7 units from f(x).
Identify the transformation that occurs to create the graph of h(x).
H(x)=f(x+3)
Answer: The graph moved left 3 units.
(x, y) = (x - 3, y)
Solve this equation log3X + log3(x-6) = log3 7
Hello!
log₃(x) + log₃(x - 6) = log₃(7) <=>
<=> log₃(x * (x - 6)) = log₃(7) <=>
<=> log₃(x² - 6x) = log₃(7) <=>
<=> x² - 6x = 7 <=>
<=> x² - 6x - 7 = 0 <=>
<=> x² + x - 7x - 7 = 0 <=>
<=> x * (x + 1) - 7 * (x + 1) = 0 <=>
<=> (x + 1) * (x - 7) = 0 <=>
<=> x + 1 = 0 and x - 7 = 0 <=>
<=> x = -1 and x = 7, x ∈ { 6; +∞ } <=>
<=> x = 7
Good luck! :)
In triangle ABC , segment AB is congruent to segment CB . Which angles are congruent?
Answer:
angles A and C are congruent
Mr johnson sells erasers for $3 each. He sold 96 erasers last week and he sold 204 erasers this week.
A. $300 B $600 C $100 D $900
I believe your answer is D.) $900
204 + 96 = 300
300 x 3 = 900
I hope this is correct and helps!
Which description of the graph of the linear inequality y > 3x – 8 is correct?
Options :
A.The graph will be a dashed line with a y-intercept of negative eight and a slope of three. The graph will be shaded below the line
B.The graph will be a solid line with a y-intercept of three and a slope of negative eight. The graph will be shaded above the line.
C. The graph will be a solid line with a y-intercept of three and a slope of negative eight. The graph will be shaded below the line.
D.The graph will be a dashed line with a y-intercept of negative eight and a slope of three. The graph will be shaded above the line
Answer:
D.The graph will be a dashed line with a y-intercept of negative eight and a slope of three. The graph will be shaded above the line
Step-by-step explanation:
The equation y > 3x – 8
Interpreting as a linear relation :
y > ax + b
Where, a = slope ; b = intercept
a = 3 ; that is a slope value of 3
b = -8 ; that is an intercept value of - 8
Since the inequality is >, a dashed line is used (dashed like is used for > and <) ; since we a have a greater than sign, the graph will be shaded above the dashed line.
Answer: The answer is D on edu 2021
Step-by-step explanation:
D.The graph will be a dashed line with a y-intercept of negative eight and a slope of three. The graph will be shaded above the line
Assume that the breaking system of a train consists of two components connected in series with both of them following Weibull distributions. For the first component the shape parameter is 2.1 and the characteristic life is 100,000 breaking events. For the second component the shape parameter is 1.8 and characteristic life of 80,000. Find the reliability of the system after 2,000 breaking events:
Answer:
0.9984
Step-by-step explanation:
we have shape parameter for the first component as 2.1
characteristics life = 100000
for this component
we have
exp(-2000/100000)².¹
= e^-0.0002705
= 0.9997
for the second component
shape parameter = 1.8
characteristic life = 80000
= exp(-2000/80000)¹.⁸
= e^-0.001307
= 0.9987
the reliability oif the system after 2000 events
= 0.9987 * 0.9997
= 0.9984
8. Discount: An auto dealer paid $8730 for a
large order of special parts. This was not the
original price. The amount paid reflects a 3%
discount off the original price because the
dealer paid cash. What was the original price
of the parts?
Answer: 5,987
Step-by-step explanation:
At the Fidelity Credit Union, a mean of 5.8 customers arrive hourly at the drive-through window. What is the probability that, in any hour, more than 5 customers will arrive
Answer:
0.5217
Step-by-step explanation:
P(more than 5 customer arrive):
P(X>=6)=1-P(X<=5)= 1-∑x=0x e-λ*λx/x!= 0.5217
Suppose that you are interested in determining the average height of a person in a large city. You begin by collecting the heights of a random sample of 196 people from the city. The average height of your sample is 68 inches, while the standard deviation of the heights in your sample is 7 inches. The standard error of your estimate of the average height in the city is
Answer:
The standard error of your estimate of the average height in the city is 0.5 inches.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
You begin by collecting the heights of a random sample of 196 people from the city.
This means that [tex]n = 196[/tex]
The standard deviation of the heights in your sample is 7 inches.
This means that [tex]\sigma = 7[/tex]
The standard error of your estimate of the average height in the city is
[tex]s = \frac{\sigma}{\sqrt{n}} = \frac{7}{\sqrt{196}} = 0.5[/tex]
The standard error of your estimate of the average height in the city is 0.5 inches.
