Answer:
she scored 76 percent in the test
3x^2 - 4x + 2 = 0
how many solutions does the equation above have?
A random sample of items is selected from a population of size . What is the probability that the sample mean will exceed if the population mean is and the population standard deviation eq
Answer:
The probability is 1 subtracted by the p-value of [tex]Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex], in which X is the value we want to find the probability of the sample mean exceeding, [tex]\mu[/tex] is the population mean, [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
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.
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.
Central Limit Theorem for the sample mean:
Sample of size n, and thus:
[tex]s = \frac{\sigma}{\sqrt{n}}[/tex]
[tex]Z = \frac{X - \mu}{s} = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
Probability of the sample mean exceeding a value:
The probability is 1 subtracted by the p-value of [tex]Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex], in which X is the value we want to find the probability of the sample mean exceeding, [tex]\mu[/tex] is the population mean, [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Please Find the value of x and y
Answer: x=40° and y=140°
Step-by-step explanation:
From the figure, we know that x and 40 are vertical angles. Therefore, they are equal to each other.
x=40°
With the value of x, we know that x and y are supplementary angles. That means they are equal to 180°.
40+y=180 [subtract both sides by 40]
y=140°
Now we know x=40° and y=140°.
What is the volume of the solid figure?
152 cubic ft
Answer:
Volume of solid figure=Volume of
upper cuboid+volume of lower cuboid
=l*b*h+l*b*h=10*4*3+4*4*2=152 cubic ft
152 cubic ft
Answer:
Volume of solid figure=Volume of
upper cuboid+volume of lower cuboid
=l*b*h+l*b*h=10*4*3+4*4*2=152 cubic ft
SOMEONE HELP ME PLEASE
Answer:
The missing value is 5/2
Step-by-step explanation:
Margot surveyed a random sample of 180 people from the United States about their favorite sports to watch. Then she sent separate, similar, survey to a random sample of 180 people from the United Kingdom. Here are the results:
Favorite sport to watch United States United kingdom Total
Basketball 60 51 111
Football 67 14 81
Soccer 28 86 114
Tennis 25 29 54
Total 180 180 360
Margot wants to perform a x^2 test of homogeneity on these results. What is the expected count for the cell corresponding to people from the United Kingdom whose favorite sports to watch is tennis?
Answer:
27
Step-by-step explanation:
The expected count in a χ² test can be obtained thus :
Expected count for each each point in a two way table ::
(row total * column total) / total
Therefore, expected count for cell corresponding to people from United Kingdom whose favorite sport is tennis :
Row total = (51+14+86+29) = 180
Column total = (25 + 29) = 54
Total = 360
Hence,
Expected count = (180 * 54) / 360
Expected count = 27
Plz help me solve this thanks
Answer:
[tex]-2\sqrt{3}+8\sqrt{5}[/tex]
Step-by-step explanation:
[tex]-2\sqrt{3} -\sqrt{5} +3\sqrt{9\times5} = -2\sqrt{3} -\sqrt{5} +3\sqrt{9}\times\sqrt{5} = -2\sqrt{3} -\sqrt{5} +9\sqrt{5} = -2\sqrt{3}+8\sqrt{5} \\[/tex]
If there is an 10+ lax
on a $25 pair of pants
what is the tax
amount?
Answer:
A 6% sales tax.
Step-by-step explanation:
Complete the problems in measurements. Show answers in simplest terms.
e. Joseph has a bag of dog food that weighs 5 lb. He wants to feed his dog 7 oz. of dog food per day, How many days will the bag of dog food last?
A hot air balloon is cruising at an altitude of 120 meters above the ground when it begins its descent. The balloon descends at a rate of 4.5 meters per minute. Explain how you would set up an equation to model when the balloon will reach an altitude of 75 meters above the ground. Then solve the equation and check your solution.
PLEASE HELP ASAP
Answer:
y = - 4.5x + 120
75 = - 4.5x + 120
x = 10 minutes
Step-by-step explanation:
To model the scenario described above, we use the linear equation model ;
Where ;
y = bx + c ; c = intercept ; b = slope ; y = altitude at time x
The initial altitude of the hot air Ballon here is the intercept = 120 meters
The descent rate = 4.5 m per minute is the slope ; since it is descent, then the slope will be negative as the altitude will reduce.
Hence, we have ;
y = - 4.5x + 120
Hence, the time altitude will be 75 cabnbe modeled as :
y = 75
75 = - 4.5x + 120
75 - 120 = - 4.5x
- 45 = - 4.5x
x = 10 minutes
The graphs below show measurements from cubes
with different side lengths.
Which pairs of variables have a linear relationship?
Select two options.
24
side length and perimeter of 1 face
20
perimeter of 1 face and area of 1 face
16
Perimeter of 1 Face
surface area and volume
A
area of 1 face and surface area
side length and volume
1
2
3
4
5
6
Side Length
40
36
32
Answer:
the first one and the third one
Step-by-step explanation:
Answer:
Side length and perimeter of 1 face
Area of 1 face and surface area
Step-by-step explanation:
Some one help me with this pls!!!
Answer:
V = 2,495.5 ft³
Step-by-step explanation:
Volume of the given cylinder = πr²h
Where,
π = 3.14
radius (r) = ½(17) = 8.5 ft
height (h) = 11 ft
Plug in the values into the formula
V = 3.14 × 8.5² × 11
V = 3.14 × 72.25 × 11
V = 2,495.515
V = 2,495.5 ft³ (to nearest tenth)
Someone please help I have 40 mins for this test !
Answer:
It would be Linear
Step-by-step explanation:
Answer:
i think its quadratic because the graph isnt straight and has different slopes between the x,y.
Step-by-step explanation:
The vertex of this parabola is at (-5, -2). When the x-value is -4, the
y value is 2. What is the coefficient of the squared expression in the
parabola's equation?
(-5,-2)
© A. 1
O B. -1
C. 5
D. 4
Hey again I need some help I would really appreciate it
Answer:
127 degree
Step-by-step explanation:
because angle 6 is alternate to 127 degree. Alternate makes a=b which is angle 6 is equal to 127 degree
What is the MAXIMUM of the data set: 24, 25, 29, 30, 31, 31, 32, 34, 34?
how is 470000000 written in scientific notation
Answer:
4.7 * 10^8
Step-by-step explanation:
4
3. Fred used 1 1/6cups of raisins, and 3 1/3cups
of nuts to make his trail.mix. How many
cups of the mix did he make?
Based on the cumulative frequency histogram, determine the number of swimmers who swam between 200 and 249 yards. Determine the number of swimmers who swam between 150 and 199 yards. Determine the number of swimmers who took the swim test.
Answer:
[tex](a)\ 200 \to 249 =3[/tex]
[tex](b)\ 150 \to 199 = 0[/tex]
[tex](c)\ Total = 20[/tex]
Step-by-step explanation:
Given
See attachment for cumulative frequency histogram
Solving (a): Swimmers between 200yd and 249yd
To do this, we simply read the data from the 0 mark
From the histogram, we have:
[tex]0 \to 249 = 15[/tex]
and
[tex]0 \to 199 = 12[/tex]
So:
[tex]200 \to 249 = 0 \to 249 - 0 \to 199[/tex]
This gives:
[tex]200 \to 249 = 15-12[/tex]
[tex]200 \to 249 =3[/tex]
Solving (b): Swimmers between 150yd and 199yd
To do this, we simply read the data from the 0 mark
From the histogram, we have:
[tex]0 \to 149 = 12[/tex]
and
[tex]0 \to 199 = 12[/tex]
So:
[tex]150 \to 199 = 0 \to 199 - 0 \to 149[/tex]
This gives:
[tex]150 \to 199 = 12-12[/tex]
[tex]150 \to 199 = 0[/tex]
Solving (c): Total swimmers
To do this, we simply read the longest bar of the histogram
[tex]Longest = 20[/tex]
Hence:
[tex]Total = 20[/tex]
help me fast plsssdsssssss
Please help me with this question
9514 1404 393
Answer:
D(1, 2)
Step-by-step explanation:
The ordered pair is always (x-coordinate, y-coordinate).
The x-coordinate is the distance to the right of the y-axis. (It is negative for points left of the y-axis.) Here, point D lies 1 unit right of the y-axis, so its x-coordinate is 1.
The y-coordinate is the distance above the x-axis. (It is negative for points below the x-axis). Here, point D lies 2 units above the x-axis, so its y-coordinate is 2.
The ordered pair describing the location of D is ...
(x-coordinate, y-coordinate) = (1, 2)
in a random sample of 28 people, the mean commute time to work was 31.2 minutes and the standard deviation was 7.3 minutes. assume the population is normally distributed and use a t-distribution to construct a 99% confidence interval for the population mean u. What is the margin of error of u
Answer:
The margin of error of u is of 3.8.
The 99% confidence interval for the population mean u is between 27.4 minutes and 35 minutes.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 28 - 1 = 27
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 27 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 2.7707
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.7707\frac{7.3}{\sqrt{28}} = 3.8[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error of u is of 3.8.
The lower end of the interval is the sample mean subtracted by M. So it is 31.2 - 3.8 = 27.4 minutes
The upper end of the interval is the sample mean added to M. So it is 31.2 + 3.8 = 35 minutes
The 99% confidence interval for the population mean u is between 27.4 minutes and 35 minutes.
Find the value of X
Answer:
100°
Step-by-step explanation:
the lower right angle is 180-149 = 31°
the sum of all three angles in a triangle is 180°.
so the solution is 180-31-49
convert fraction to decimal 7over 21 need help now
Answer:
0.33333
Step-by-step explanation:
That's the answer to this
Which statement must be true about line TU?
Answer:
wer: The true statement is 'Line TU is parallel to line RS'. Explanation: Since, we know that if a line is perpendicular to two different lines then these two different lines must be parallel to each other. Here, it is given that WV is perpendicular to both lines RS and TU. Therefore, RS must be parallel to TU.
A hotel spent $504 on new hair dryers. The hair dryers cost $8 each. The hotel has 6 floors with the same number of rooms on each floor. If every room gets a new hair dryer, how many hair dryers will be left over?
Answer:
3
Step-by-step explanation: 6 11 10 48
spent $504
hair dryers cost $8 each
6 floors with the same number of rooms on each floor.
Money spent / hair dry cost = number of hair dryers bought
number of hair dryers = number of floors = hair dryers per floor Plus any remainder
504 / 8 = 63 hair dryers
63 / 6 = 10.5 so 10 rooms per floor = 60 hairs dryers with 3 left over
Answer:
well IMA just copy the other guy and say 3
Step-by-step explanation:
just cause it is.
3. Find the measure of the exterior angle in the diagram below.
Answer:
the value of x is 29° which is b
Help with this Geometry question please
Answer:
Angle A = [tex]77^{o}[/tex]
Step-by-step explanation:
cos A = adjacent / hypotenuse
cos A = 18/82
cos A = 0.22
A = [tex]cos ^{-1}[/tex]0.22
A = [tex]77^{o}[/tex]
I need the answer to #3
Answer:
I think its b but im not sure
Step-by-step explanation:
A segment has endpoints A and C. What are two names for the segment?
Answer:
Ac CA is your answer
Step-by-step explanation:
MARK ME AS BRAINLIEST
AC and CA
Step-by-step explanation:
[tex]line \: which \: has \: endpoint \: \\ \\ A \: and \: C \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ it \: shows \: that \: line \: starts \: from \: \\ \\ A \: \: and \: ends \: with \: C \\ \\ so \: \: its \: name \: is \: \: \: \: AC \\ \\ hope \: it \: is \: helpful \: to \: you....[/tex]
