Answer:
El tejado tenía un ancho de 31.4 m.
Step-by-step explanation:
Tenemos un techo rectangular, con un largo de 29.7 m y un ancho x, que debemos calcular.
Entonces, la superficie del tejado es:
[tex]S=29.7x\;\,\text{[m}^2\text{]}[/tex]
Las locetas tienen una superficie de 25x19 cm, de las cuales 1/5 se pierde en la colocación. La superficie eficaz que ocupa cada loceta una vez colocada es:
[tex]S_L=(25\cdot19)\cdot(1-1/5)=475\cdot(0.8)=380\;\text{cm}^2[/tex]
Entonces, si se utilizaron 24552 locetas para cubrir todo el techo, podemos expresar la superfice del techo como:
[tex]S=24552\;\text{locetas}\;\cdot380\dfrac{\text{cm2}}{\text{loceta}}\cdot \left(\dfrac{1\text{m}}{100\text{cm}}\right)^2=\dfrac{24552\cdot380}{10000}\;\text{m2}=932.976\;\text{m2}[/tex]
Podemos calcular x igualando este último resultado con la primer ecuación:
[tex]S=29.7x=932.976\\\\x=932.976/29.7=31.413\approx31.4[/tex]
The waiting times between a subway departure schedule and the arrival of a passenger are uniformly distributed between 0 and 9 minutes. Find the probability that a randomly selected passenger has a waiting time greater than 1.25 minutes.
Answer:
P(greater than 1.25 minutes) = 0.8611 (Approx)
Step-by-step explanation:
Given:
Waiting time = 0 - 9 minutes
Find:
Probability that selected passenger has a waiting time greater than 1.25 minutes.
Computation:
⇒ The probability that a randomly selected passenger has a waiting time greater than 1.25 minutes =
⇒ P(greater than 1.25 minutes) = [9-1.25] / 9
⇒ P(greater than 1.25 minutes) = [7.75] / 9
⇒ P(greater than 1.25 minutes) = 0.8611 (Approx)
Plz help. Dora calculated the mean absolute deviation for the data set 35, 16, 23, 42, and 19. Her work is shown below. Step 1: Find the mean. mean = StartFraction 35 + 16 + 23 + 42 + 19 Over 5 EndFraction = 27 Step 2: Find each absolute deviation. 8, 11, 4, 15, 8 Step 3: Find the mean absolute deviation. M A D = StartFraction 8 + 11 + 4 + 15 Over 5 EndFraction = 9.5 What is Dora’s error?
A. Dora should have divided by 4 when finding the mean
B. Dora found the absolute deviation of 35 incorrectly
C. Dora used only four numbers in finding the mean
D. Dora used only four numbers in finding the mean absolute deviation
Answer:
step 3 is wrong
Step-by-step explanation:
i know it because i did the unit test review
Answer:
D
ヾ(•ω•`)o
Step-by-step explanation:
9.2 An electrical firm manufactures light bulbs that have a length of life that is approximately normally distributed with a standard deviation of 40 hours. If a sample of 30 bulbs has an average life of 780 hours, find a 96% confidence interval for the population mean of all bulbs produced by this firm.
Answer:
765,795 = 96%
Step-by-step explanation:
confidence interval = 0.04
The Za/2 theorem = 1/2 = 0.04/2 = 0.02= /x = 720z
If ; 0.02 = 2.05 then the interval is 780-2.05 x 40/√30 x 780+2.05 x 30/√30 = 765,795 = 96%
We see 40/ √30 which is found in equation of finding the sample mean at point /x = 720z
σ 40/ n√30 = 7.3029674334 and is simply a fraction of /x 720z
By normal distribution we find
The 96% confidence interval for the population mean of all bulbs = 765,795
As 765, x 1.04 = 795 = 765, 795
To find Sampling mean.
The Sampling Distribution of the Sample Mean. If repeated random samples of a given size n are taken from a population of values for a quantitative variable, where the population mean is μ (mu) and the population standard deviation is σ (sigma) then the mean of all sample means (x-bars) is population mean μ (mu).
Confidence Level z*-value
80% 1.28
90% 1.645 (by convention)
95% 1.96
96% 2.05
98% 2.33
99% 2.58
is the square root of 5/8 rational or irrational
Answer:
the answer is square root 5 over 2 square root 2
Step-by-step explanation:
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
B. F(x) = 0.4x² - 1
Step-by-step explanation:
→The function F(x) has shifted downwards, meaning there has to be a 1 being subtracted.
→The function F(x) has grown wider, meaning there has to be a number of absolute value less than 1.
This means answer choice, "B," is correct.
Answer:
The answer is B
Step-by-step explanation:
→The function F(x) has shifted downwards, meaning there has to be a 1 being subtracted.
→The function F(x) has grown wider, meaning there has to be a number of absolute value less than 1.
This means answer choice, "B," is correct.
According to exit polls, the voting "gender gap" was 22 points in the 2016 House of Representatives election; that is, women voted for Democrats by 10 percentage points, and men voted for Republicans by 12 percentage points. Political scientists are curious to see if this gap holds- or increases- in 2018, but statisticians might be more interested in the processes behind exit polling and the rellabllity of thelr results.
When conducting exit polls, pollsters will randomly select a certain number of precincts, then attempt to get all the voters leaving the polling place to participate in their poll. If they can't get all voters, they will instead attempt to get every nth voter to participate. Many polling companies believe that Democrats are more likely to agree to an exit poll than Republicans or Independents.
Of course, not everyone votes in the morning/mid-afternoon of the election. To get an idea of the preferences of people who voted in the precinct before election day, typically by absentee ballots, companies will attempt a random telephone survey of those voters. Exit polls often wrap up and leave the field before voting stations close, so people voting in the last couple hours of the day may also be missed
(a) What type of sampling methods are used in selecting people for exit polls?
a. Simple Random Sampling
b. Cluster Sampling
c. Stratified Sampling
d. Convenience Sampling
e. Systematic Sampling
(b) Why do the polllng companles randomly select the preclncts to vislt?
a. Randomly selecting precincts to assign pollsters ensures that the companies can conclude a cause and effect relationship between the voters' beliefs and their voting pattern
b. There are too many precincts to manually select, so they are forced to randomly select them
c. Randomly selecting precincts increases the likelihood that the people polled represent the population well.
Answer:
A) cluster sampling ( b ) and systematic sampling ( e )
B ) Randomly selecting precincts increases the likelihood that the people polled represent the population well. ( c )
Step-by-step explanation:
Cluster sampling is a type of sampling plan used when there is an internally heterogeneous groups can be found inside a population that is supposed to be mutually homogeneous . while systematic sampling is a type of probability sampling that involves the selection of samples from a larger population at random but using a specific interval. to get the systematic sample the larger population is divided by the sample size.
from the information available in the report it is very evident that not all voters can be captured at once hence cluster sampling and systematic sampling would be employed .
B) the company will randomly select precinct to increase the likelihood of the sample size representing the entire population very well
A grocery store has a discount of 13% off hand soap. At the same time the hand soap manufacturer has a coupon for $2.00 off. Assuming both promotions can be applied at the same time how much more would you pay if you applied the coupon first?
Answer:
[tex]\$0.26[/tex] has to be paid more if the coupon is applied first
Step-by-step explanation:
Given: A grocery store has a discount of 13% off hand soap. At the same time the hand soap manufacturer has a coupon for $2.00 off.
To find: how much more would be paid if the coupon is applied first
Solution:
Let $ x denotes cost of hand soap
Case 1:
If the discount is given first,
cost of hand soap = [tex]x-\frac{13}{100} x=\$ \frac{87}{100}x[/tex]
If the coupon for $2.00 off is applied,
Final cost of the hand soap = [tex]\$\,(\frac{87}{100}x-2)[/tex]
Case 2:
If the coupon for $2.00 off is applied first,
cost of hand soap = [tex]\$(x-2)[/tex]
If the discount is given then,
final cost of the hand soap = [tex](x-2)-\frac{13}{100}(x-2)=\frac{87}{100}(x-2)[/tex] = [tex]\frac{87}{100}x-\frac{87}{50}[/tex]
Here,
[tex]\frac{87}{100}x-\frac{87}{50}-\frac{87}{100}x+2=\frac{13}{50}=\$0.26[/tex]
So, [tex]\$0.26[/tex] has to be paid more if the coupon is applied first.
Answer:
$0.26
Step-by-step explanation: I took the test
The yearbook club is handing out T-shirts to its members. There are 5 blue, 7 green, 9 red, and 4 yellow T-shirts in all. If Jacob is handed a T-shirt, what is the probability that the color is red? 925 916 35 1625
Answer:
9/25
Step-by-step explanation:
Don't worry, I just took this test and got it correct. Best of luck to you all!
2x2 + 3x ANSWER TO THIS
Answer:
x(2x+3)
Step-by-step explanation:
Im guessing 2x2 is 2x^2
2x^2 + 3x = 0
x(2x+3)
x=(y+2)^2 solve the equation
Answer:
x= y^2+4y+4
Step-by-step explanation:
x= (y+2)(y+2)
x= y^2+2y+2y+4
x= y^2+4y+4
Answer:
X = y^2 + 4y + 4
Y= (√X) -2
Step-by-step explanation:
X = (Y+2)^2
X = (Y+2)(Y+2)
X = Y^2 + 4y + 4
X = (Y+2)^2
√X = √(Y+2)^2 (taking the root of both sides cancels the exponent)
√X = Y+2
-2 -2
(√X) - 2 = Y
or
Y = (√X) - 2
Working on Summer Vacation. An Adweek/Harris (July 2011) poll found that 35% of U.S. adults do not work at all while on summer vacation. In a random sample of 10 U.S. adults, let x represent the number who do not work during summer vacation
a. For this experiment, define the event that represents a "success"
b. Explain why x is (approximately) a binomial random variable
c. Give the value of p for this binomial experiment
d. Find P(x = 3)
e. Find the probability that 2 or fewer of the 10 U.S. adults do not work during summer vacation
A becuase i worked it out and i got that so im really confident
Tom wants new carpeting for his bedroom. His room is a 9 metres by 7 metres rectangle.
How much carpeting does he need to buy to cover his entire bedroom floor
Answer:
63
Step-by-step explanation:
So just find the area of the carpet:
9 * 7 = 63
Austin is 103 years old Raquel is 35 years old how many years ago was Austin age 5 times Raquel age
Answer:
18
Step-by-step explanation:
Let x represent the years ago
103-x = 5(35-x)
103-x = 175 +5x
4x = 72
x = 18
Which operation is the default operation in algebra?
Step-by-step explanation:
in mathematics, a basic algebra corporation is there any one of the traditional operation of arithmetic, which are addition, subtraction, multiply, division, rising to an integer power, and taking root (fractional power ).
a pail holds 3 1/2 gallons of water. How much is it in cups
Answer:
3 1/2 gallons of water is 56 cups
Step-by-step explanation:
Answer:
14
Step-by-step explanation:
1 gallon=4cups
1/2 gallon=2cups
3*4=12
or 4cups+4cups+4cups=12
12+2=14
Two machines used to fill soft drink containers are being compared. The number of containers filled each minute is counted for 60 minutes for each machine. During the 60 minutes, machine 1 filled an average of 73.8 cans per minute with a standard deviation of 5.2 cans per minute, and machine 2 filled an avaerage of 76.1 cans per minute with a standard deviation of 4.1 cans per minute.
Required:
a. If the counts are made each minute for 60 consecutiveminutes, what assumption necessary to the validity of a hypothesistest may be violated?
b. Assuming that all necessary assumptions are met, perform a hypothesis test. Can you conclude that machine 2 is faster than machine 1?
Answer:
The calculated value |t| = | - 2.6932 | = 2.6932 > 1.9803 at 0.05 level of significance
Alternative hypothesis is accepted
The average of machine two is faster than machine one
Step-by-step explanation:
Step(i):-
Given sample size n₁ = n₂ = 60 minutes
The average of first sample 'x⁻₁ = 73.8
The standard deviation of the first sample 'S₁ ' = 5.2 cans per minute
The average of second sample 'x⁻₂ = 76.1
The standard deviation of the second sample 'S₂ ' = 4.1 cans per minute
step(ii):-
Null Hypothesis : H₀: 'x⁻₁ = 'x⁻₂
Alternative Hypothesis : H₁ : 'x⁻₁ > 'x⁻₂
Test statistic
[tex]t = \frac{x^{-} _{1} - x^{-} _{2} }{\sqrt{\frac{S^{2} _{1} }{n_{1} } +\frac{S^{2} _{2} }{n_{2} } } }[/tex]
[tex]t = \frac{73.8 - 76.1 }{\sqrt{\frac{(5.2)^{2} }{60 } +\frac{(4.1)^{2} }{60 } } }[/tex]
t = - 2.6932
|t| = | - 2.6932 | = 2.6932
Step(iii):-
Degrees of freedom
ν = n₁ + n₂ -2 = 60 +60 -2 = 118
t₀.₀₅ = 1.9803
The calculated value |t| = | - 2.6932 | = 2.6932 > 1.9803 at 0.05 level of significance
Final answer:-
Null hypothesis is rejected at 0.05 level of significance
Alternative hypothesis is accepted
The average of machine two is faster than the average of machine one
Determine the number of ways three trumpet players out of 6 are chosen for 1st chair, 2nd chair, and 3rd chair.
Answer:
120 ways
Step-by-step explanation:
There are 3 spots and 6 options
_ _ _
1 2 3
6 ways for 1st chair to be chosen
5 ways for 2nd chair to be chosen (1st chair is chosen already, so there are 5 players left)
4 ways for 3rd chair to be chosen (1st and 2nd are already chosen, only 4 players left)
Multiply 6*5*4 to find the total number of ways (120)
Find the slope of the line on the graph.
Write your answer as a fraction or a whole
number, not a mixed number or decimal.
Answer:
1
Step-by-step explanation:
divide vertical drop by horizontal drop
or vertical increase by horizontal increase
for example, in the graph when y increases by 1 x increases by 1
1/1=1 and thus the gradient is 1
the whole equation is y=x+3
Answer:
The slope = 1.
Step-by-step explanation:
If we count squares down for the top arrow then left to the point where the line cuts the horizontal axis we get 10 and 10.
So the slope = 10/10 = 1.
Deepak is a landscaper who charges $30 for each job he does plus an additional $15 for each hour he works. He only accepts jobs if he will earn at least $90 the job. He writes this inequality to determine x, the number of hours he must work during each job in order to accomplish this.
30 + 15 x greater-than-or-equal-to 90
Which best describes the restrictions on the jobs Deepak will accept?
He only accepts jobs that last 4 or more hours.
He only accepts jobs that last 5 or more hours.
He only accepts jobs that last 8 or more hours.
He only accepts jobs that last 9 or more hours.
Hey there! I'm happy to help!
The only thing we have to do is solve our inequality to find the answer!
30+15x ≥ 90
We subtract 30 from both sides.
15x ≥ 60
Finally, we divide both sides by four.
x ≥ 4
Therefore, Deepak can only accept jobs that last 4 or more hours.
I hope that this helps! Have a wonderful day!
The solution for the inequality is x≥4. Therefore, option A is the correct answer.
Given that, Deepak is a landscaper who charges $30 for each job he does plus an additional $15 for each hour he works.
What are inequalities?Inequalities are the mathematical expressions in which both sides are not equal. In inequality, unlike in equations, we compare two values. The equal sign in between is replaced by less than (or less than or equal to), greater than (or greater than or equal to), or not equal to sign.
The inequality for the given situation is 30+15x≥90
Subtract 30 on the both the sides of an inequality, which is
30+15x-30≥90-30
⇒ 15x≥60
Divide 15 on the both the sides of an inequality, that is
15x/15≥60/15
⇒ x≥4
The solution for the inequality is x≥4. Therefore, option A is the correct answer.
To learn more about the inequalities visit:
https://brainly.com/question/20383699.
#SPJ5
(DONT REPORT OR ANSWER) pls don’t (what is -2 plus -2)
Answer:
I think it’s -4
Step-by-step explanation:
-2 plus -2 is -4
since 2 plus 2 is 4
Hope this helps ;)
Answer:
It is -4Step-by-step explanation:
It is because 2 plus 2 is 4
so -2 plus -2 is -4
hth!
(x-5)(x+1)=x-5 3(x+1) 3 For what values of x are the two expressions equal ?
Answer:
x=-77+5√ 231 x=-77-5√231
I got this answer for x and the both equations are equal
the sum of the measures of the angles of any triangle is 180 degrees. in triangle ABC, angles A and B have the same measure, of bile the measure of angle C is 72 degrees larger than each of A and B. what are the measures of the three angles?
Answer:
A=36
B=36
C=108
Step-by-step explanation:
A =B
2A+C=180
C is greater than A
2A+(A+72) =180
SIMPLIFY
3A +72=180
-72 ON BOTH SIDES
3A=108
DIVIDE BY 3
A=36
SO
B=36
36 TIMES 2 IS 72
180-72=108
SO
C=108
hope this helps
Answer:
Angle C= 108
Angles A and B=36
Step-by-step explanation:
180-72=108
108-72= 36
Check
36+36=72
72+108=180
What’s the correct answer for this question?
Answer:
3724 in^3
Step-by-step explanation:
19 times 14 times 14 = 3724
Answer:
3724 inches ³
Step-by-step explanation:
Volume of cooler = whl
Where w is width, h is height and l is length
V = (19)(14)(14)
V = 3724 inches³
Fuel Efficiency of Cars and Trucks Since 1975 the average fuel efficiency of U.S. cars and light trucks (SUVs) has increased from 13.5 to 25.8 mpg, an increase of over 90%! A random sample of 40 cars from a large community got a mean mileage of 28.1 mpg per vehicle. The population standard deviation is 4.7 mpg. Estimate the true mean gas mileage with 95% confidence.
Answer:
[tex]28.1-1.96\frac{4.7}{\sqrt{40}}=26.64[/tex]
[tex]28.1+ 1.96\frac{4.7}{\sqrt{40}}=29.56[/tex]
We are confident at 95% of confidence that the true mean for the mpg is between 26.64 and 29.56. And since the lower limit from the confidence interval is highert than 25.8 then we can conclude that we have a significant increase from 1975
Step-by-step explanation:
Information given
[tex]\bar X= 28.1[/tex] represent the sample mean
[tex]\mu[/tex] population mean
[tex]\sigma =4.7[/tex] represent the population standard deviation
n=40 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (1)
The Confidence level is is 0.95 or 95%, the significance would be [tex]\alpha=0.05[/tex] and [tex]\alpha/2 =0.025[/tex], and we can calculate the critical value using the normal standard distribution and we got [tex]z_{\alpha/2}=1.96[/tex]
And replacing we got:
[tex]28.1-1.96\frac{4.7}{\sqrt{40}}=26.64[/tex]
[tex]28.1+ 1.96\frac{4.7}{\sqrt{40}}=29.56[/tex]
We are confident at 95% of confidence that the true mean for the mpg is between 26.64 and 29.56. And since the lower limit from the confidence interval is highert than 25.8 then we can conclude that we have a significant increase from 1975
3. Find the mean and range of the following data.
14, 14, 15, 15, 16, 15, 15, 16
A 15; 15
B 12; 15
C 12; 2
D 15; 2
Answer:
D: 15 and 2
Step-by-step explanation:
Mean
To find the mean, or average, add up all the values in the data set,then divide by the number of values in the data set.
1. Add up all the values
Values: 14, 14, 15, 15, 16, 15, 15, 16
Add them :14+14+15+ 15+16+15+15+16=120
120
2. Divide by the number of values
Count how many numbers are in the data set. In this case there are 8. Divide 120 by 8.
120/8=15
The mean is 15
Range
To find the range, subtract the smallest number in the set from the biggest number in the set.
14, 14, 15, 15, 16, 15, 15, 16
Biggest number: 16
Smallest number: 14
biggest-smallest
16-14=2
The range is 2
Therefore, the answer is D: 15 and 2
observation means number.
mean= sum of all observation ÷ number of observation
= 14+ 14+ 15+ 15+ 16+ 15+ 16
7
= 105
7
= 15
range= the highest observation - lowest observation
= highest number- 16
lowest number- 14
= 16-14
= 2
therefore the answer is
OPTION- D 15;2
are all the rectangles faces the same size
Answer:
A rectangle is a 2 dimensional figure, it is in a plane, so it has two faces, and yes, they are equals.
Find x in this 45°-45°-90° triangle.
145972
x
X=
4.572
9
18
What’s the correct answer for this question?
Answer:
A.
Step-by-step explanation:
In the attached file
The equation 4x-45=y is used to find your profit y in dollars from buying $45 of supplies and washing cars for $4 what does the x stand for
what is the value of this expression plssssss 8z-3 when z =7
Answer:
53
Step-by-step explanation:
8•7 is 56
56 - 3 is 53
Answer:
53
Step-by-step explanation:
z = 7
8z is the same as saying 8×z
8×7-3 (do multiplication first)
56-3 = 53
