Answer:
Step-by-step explanation:
Keywords:
System of equations, variables, cost, tickets, adults, children.
For this case we must solve a system of equations with two variables represented by the tickets of students and adults of a school production.
We define the variables according to the given table:
a: Number of tickets sold to adults
c: Amount of tickets sold to children.
We then have the following system of equations:
A + c = 67
10a + 5c =440
From the first equation, we clear the value of the variable c:
C = 67 - a
Answer:
The value that could replace c in the table is:
C = 67 - a
Option C is the answer!
Hope it helped u if yes mark me BRAINLIEST!
Tysm! Plz
jeff buys 44 watermelons, he gets into a car accident and loses 31, how many does jeff have left
Answer:
Jeff has 3 watermelons left
Step-by-step explanation:
44-31=13 watermelons
Answer:
13
Step-by-step explanation:
44
-31
13
Assume that thermometer readings are normally distributed with a mean of 0C and a standard deviation of 1.00C. A thermometer is randomly selected and tested. For the case below, draw a sketch, and find the probability of the reading. (The given values are in Celsius degrees.) Between and
Answer: 0.0546 and 0.9829
Step-by-step explanation:
solution:
= P( 1.50< Z <2.25 )
= P(Z <2.25 ) - P(Z <1.50 )
Using z table,
= 0.9878-0.9332
=0.0546
b.
= P( -2.12< Z <3.73 )
= P(Z <3.73) - P(Z <-2.12 )
Using z table,
= 0.9999-0.0170
=0.9829
_Thirty-two holes are drilled in rows on a metal block. The number of rows is more than the number of holes in each
row. Find the number of row. (a)7 (b)25(c)67
(d)4 (e) 12
_
Answer:
D
Step-by-step explanation:
Let the number of rows be x
And the numbers of holes in each be y
xy = 32
x and y must be factors of 32
From options stated
4 is the only factor of 32
Hence option D is correct
Suppose 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Required:
Is ordering a soft drink independent of ordering a square pizza? Explain
Answer:
Ordering a soft drink is independent of ordering a square pizza.
Step-by-step explanation:
20% more customers order a soft drink than pizza, therefore they cannot be intertwined.
Given: P(A)=0.5 & P(B)=.7
P(A∩B) = P(A) × P(B)
= 0.5 × .7
= 0.35
P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + .7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + .7 - 2×0.35
= 0.5
P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
P(B') = 1 - P(B)
= 1 - .7
= 0.3
P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
Yes ordering a soft drink is independent of ordering a square pizza.
We have given 50 percent of the customers at Pizza Palooza order a square pizza, 70 percent order a soft drink, and 35 percent order both a square pizza and a soft drink.
Let A: denote pizza
B: Soft drink
Then,
P(A)=0.5 and P(B)=0.7
And P(A∩B) = P(A) × P(B)
= 0.5 × 0.7
= 0.35
We know P(A∪B) = P(A) + P(B) - P(A∩B)
= 0.5 + 0.7 - 0.35
= 0.85
P(AΔB) = P(A) + P(B) - 2P(A∩B)
= 0.5 + 0.7 - 2×0.35
= 0.5
Also we know P(A') = 1 - P(A)
= 1 - 0.5
= 0.5
And P(B') = 1 - P(B)
= 1 -0.7
= 0.3
And P((A∪B)') = 1 - P(A∪B)
= 1 - 0.85
= 0.15
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A researcher wishes to see if the average weights of newborn male infants are higher than the
average weights of newborn female infants. She selects a random sample of 12 male infants and
finds the mean weight is 7.70 pounds. She selects a random sample of 9 female infants and finds
that the mean Leight is 7.80 pounds. Assume that the variables are normally distributed and the
population standard deviation is 0.5 for each group.
Using alpha=0.05 to test if the mean weight of the males is higher than the mean weight of the
females, the pvalue of the test is:
Answer:
The p-value is [tex]p-value = 0.62578[/tex]
Step-by-step explanation:
From the question we are told that
The sample size of male infant is [tex]n_1 = 12[/tex]
The sample size of female infant is [tex]n_2= 9[/tex]
The sample mean of male infant is [tex]\= x_1 = 7.70 \ lb[/tex]
The sample mean of female infant is [tex]\= x_2 = 7.80 \ lb[/tex]
The population standard deviation is [tex]\sigma = 0.5[/tex]
The significance level is [tex]\alpha = 0.05[/tex]
The null hypothesis is [tex]H_o : \mu_ 1 = \mu_2[/tex]
The alternative hypothesis is [tex]H_1 : \mu_1 > \mu_2[/tex]
The test statistics is mathematically represented as
[tex]t =\frac{\= x_1 - \= x_2 }{\sqrt{\frac{\sigma }{n_1} } + \frac{\sigma }{n_2} } }[/tex]
=> [tex]t = \frac{7.70 -7.80}{\sqrt{\frac{0.5 }{12} } + \frac{0.5 }{9} } }[/tex]
=> [tex]t = -0.3207[/tex]
From the z-table the p-value is obtained, the value is
[tex]p-value = P(Z > -0.3207) = 0.62578[/tex]
[tex]p-value = 0.62578[/tex]
Ted has to gift wrap a box of chocolates that is shaped like a triangular prism. What is the minimum amount of wrapping paper he needs?
Answer:
69.48 square inches
Step-by-step explanation:
The amount of wrapping paper needed = surface area of the triangular prism
Surface area of triangular prism is given as, area = Perimeter of triangular base*height of prism + 2(base area)
Perimeter of triangular base = sum of the 3 sides of the prism
Perimeter of base = 3.5 + 3.5 + 3 = 10 inches
Height of prism = 6 inches
Base area = ½*base of triangle * height of triangle = ½*3*3.16 = 4.74 in²
Surface area of triangular prism = [tex] 10*6 + 2(4.74) [/tex]
[tex] S.A = 60 + 9.48 = 69.48 in^2[/tex]
Amount of wrapping paper needed is 69.48 square inches .
A market survey shows that 50% of the population used Brand Z computers last year, 4% of the population quit their jobs last year, and 2% of the population used Brand Z computers and then quit their jobs. Are the events of using Brand Z computers and quitting your job independent
Answer:
the events of using Brand Z computers and quitting your job are independent.
Step-by-step explanation:
Let A be the event that the population used Brand Z computers and let B be the event that the population quit their jobs.
We are told that 50% of the population used Brand Z computers last year. Thus, the probability of event A is;
P(A) = 50% = 0.5
Also, we are told that 4% of the population quit their jobs last year. Thus the probability of event B is;
P(B) = 4% = 0.04
Since 2% of the population used Brand Z computers and then quit their jobs. Then the probability of the population used Brand Z computers and then quit their jobs is;
P(A ∩ B) = 2% = 0.02
From the law of independent events, if A and B are to be independent events, then;
P(A ∩ B) = P(A) × P(B)
Thus;
P(A ∩ B) = 0.5 × 0.04 = 0.02
This is same value as what was given in the question, thus the events of using Brand Z computers and quitting your job are independent.
PLEASE HELP WILL GIVE BRAINLIEST AND THX Which ratios have a unit rate of 3? Choose all that apply. 15/2 cups: 2 1/2 cups 1 cup: 1/4 cups 2/3 cups: 1 cup 3 3/4 cups: 2 cups 2 cups: 2/3 cups 2 1/2 cups: 5/6 cups
Answer:
15/2 cups: 2 1/2 cups
2 cups: 2/3 cups
2 1/2 cups: 5/6 cups
Step-by-step explanation:
Take and divide each by the smaller number
15/2 cups: 2 1/2 cups
First put in improper fraction form
15/2 : 5/2
Divide each by 5/2
15/2 ÷ 5/2 : 5/2 ÷5/2
15/2 * 2/5 : 1
3 :1 yes
1 cup: 1/4 cups
Divide each by 1/4 ( which is the same as multiplying by 4)
1*4 : 1/4 *1
4 : 1 no
2/3 cups: 1 cup
Divide each by 2/3 ( which is the same as multiplying by 3/2)
2/3 * 3/2 : 1 * 3/2
1 : 3/2 no
3 3/4 cups: 2 cups
Change to improper fraction
( 4*3+3)/4 : 2
15/4 : 2
Divide each side by 2
15/8 : 2/2
15/8 : 1 no
2 cups: 2/3 cups
Divide each side by 2/3 ( which is the same as multiplying by 3/2)
2 * 3/2 : 2/3 *3/2
3 : 1 yes
2 1/2 cups: 5/6 cups
Change to an improper fraction
( 2*2+1)/2 : 5/6
5/2 : 5/6
Divide each side by 5/6( which is the same as multiplying by 6/5)
5/2 * 6/5 : 5/6 * 6/5
3 : 1 yes
The 15/2 cups: 2 1/2 cups, 2 cups: 2/3 cups, and 2 1/2 cups: 5/6 cups have a unit rate of 3
What is the ratio?It is defined as the comparison between two quantities that how many times the one number acquires the other number. The ratio can be presented in the fraction form or the sign : between the numbers.
For checking: 15/2 cups: 2 1/2 cups
= (15/2)/(5/2) [2(1/2) = 5/2]
= 3
For checking: 1 cup: 1/4 cups
= 1/(1/4)
= 4
For checking: 2/3 cups: 1 cup
=(2/3)/1
= 2/3
For checking: 3 3/4 cups: 2 cups
= (15/4)(2)
= 15/8
For checking: 2 cups: 2/3 cups
= (2)/(2/3)
= 3
For checking: 2 1/2 cups: 5/6 cups
= (5/2)/(5/6)
= 3
Thus, the 15/2 cups: 2 1/2 cups, 2 cups: 2/3 cups, and 2 1/2 cups: 5/6 cups have a unit rate of 3
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Quadrilateral ABCD is similiar to quadrilateral EFGH. The lengths of the three longest sides in quadrilateral ABCD are 60 feet, 40 feet, and 30 feet long. If the two shortest sides of quadrilateral EFGH are 6 feet long and 12 feet long, how long is the 2nd longest side on quadrilateral EFGH?
Answer:
24
Step-by-step explanation:
For ABCD the three longest are:
60,40,30
60 to 40 is 20
40 to 30 is 10
so each time it's decreasing by 1/2
For EFGH the two shortest are:
6 and 12
12 to 6 is 1/2
Assuming there is a pattern
it logically would be 24
as 12(2)=24
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most appropriate. Years in which U.S. presidents were inaugurated
Answer:
Interval Level of Measurement
Step-by-step explanation:
The Interval level of measurement highlights the distances between two measurements. These distances are meaningful and could be rated as low intervals or high intervals. Intervals also indicate class and order between measurements. The inauguration of the United States President is an event that occurs 72 to 78 days after the presidential election. It is usually done as a private and public oath-taking ceremony on January 20, four years after the last presidential election. So, even if the president is on a second term, this event must be held.
The last U.S presidential election occurred on January 20, 2017, and the next one will be held on January 21, 2021. So there is an interval of four years between the last and next U.S presidential inauguration ceremony.
Consider exponential function h.
h(x) = 3x + 4
The function is always positive.
(0,5) is the y-intercept, since the graphed line never crosses the x axis, there is no x-intercept.
The function is positive and greater than 4 for all values of x
Not sure what the actual choices are on a couple of the questions. The choices would help answering.
I don't understand word problems can someone please answer it for me and I need it ASAP.
Answer:
Inequality: 3 + 1.2c
What you'd put on graph: 1 ≥ 13.50
You buy butter for $5.60 a pound. One portion of onion compote requires 1.7 oz of butter. How much does the butter for one portion cost? Round to the nearest cent.
Answer:
Butter per portion equals 60 cents .
Step-by-step explanation:
A pound of butter is worth $ 5.60.
5.60 dollars are converted to cents, 1 dollar equals 100 cents, then:
- One pound of butter equals 560 cents.
A portion of onion compote requires 1.7 oz of butter.
Convert 1.7 oz to pounds, so:
- 1.7 oz of butter equals 0.10625 pounds.
If a pound of butter is worth 560 cents, how much will 0.10625 pounds of butter be worth.
- Rule of 3 is used:
- 560 cents 1 pound butter
X cents 0.10625 pounds of butters
X = 560 * 0.10625
X = 59.5 cents
X = 60 cents per portion
if pentagon OPQRS is dilated by a scale factor or ?
from the origin to create O'P'Q'R'S: what is the ordered pair of point S'?
Answer:
Option (D) : (3.5, 8.75)
There are 47 contestants at a national dog show. How many different ways can contestants fill the first place, second place, and third place positions?
Answer:
97290
Step-by-step explanation:
47 different people can win first
47
Now there are only 46 people left
46 different people can win second
46
45 different people can win third
47*46*45
97290
Find the indicated complement. A certain group of women has a 0.12% rate of red/green color blindness. If a woman is randomly selected, what is the probability that she does not have red/green color blindness?
Answer:
the probability will be 0.
Step-by-step explanation:
0.12%= 0.0012= 3/2500.
Which polynomial function has zeros when ? A: B: C: D:
Which equation demonstrates the additive identity property?
Answer:
See Explanation
Step-by-step explanation:
The options are not given; however, you can take a clue from my explanation to answer your question
Let x be a real number;
Additive identity property implies that; adding x to 0 or 0 to x gives x;
In other words;
[tex]x + 0 = x[/tex]
[tex]0 + x = x[/tex]
Note that x can be replaced with any real number; Take for instance
[tex]1 + 0 = 1[/tex]
[tex]0 + 2.5 = 2.5[/tex]
[tex]3 + 0 = 3[/tex]
There are uncountable number of examples;
However, take note that adding 0 to a given digit results in the exact digit and that's the implication of addition identity property
Answer:
(7+4i)+0=7+4i
Step-by-step explanation:
If x represents the rate that Joy traveled at for the first half of the trip, write an
expression that represents the amount of time it takes Joy to complete the second half of the
trip at the slower rate.
Answer:
time taken for trip 2nd half > time taken for trip 1st half
Step-by-step explanation:
Let the total distance of Joy's trip be = D
Then, the first half distance travelled = D/2
The rate (speed) at which Joy travels during first half = x
So, time taken to travel first half = Distance / Speed
= (D/2) / x = D / 2x
Second half of trip distance travelled = remaining D/2Let the rate (speed) at which Joy travels during second half = x'
As given, x' (second half speed) < x (first half speed)
So, time taken to travel first half = Distance / Speed
(D/2) / x' = D / 2x'
As x' < x : D / 2x' > D / 2x .
Trip 1st half Time taken trip < 2nd half ; or trip 2nd half time taken > 1st half
A random sample of 12 supermarkets from Region 1 had mean sales of 84 with a standard deviation of 6.6. A random sample of 17 supermarkets from Region 2 had a mean sales of 78.3 with a standard deviation of 8.5. Does the test marketing reveal a difference in potential mean sales per market in Region 2? Let μ1 be the mean sales per market in Region 1 and μ2 be the mean sales per market in Region 2. Use a significance level of α=0.02 for the test. Assume that the population variances are not equal and that the two populations are norm
Answer:
We conclude that there is no difference in potential mean sales per market in Region 1 and 2.
Step-by-step explanation:
We are given that a random sample of 12 supermarkets from Region 1 had mean sales of 84 with a standard deviation of 6.6.
A random sample of 17 supermarkets from Region 2 had a mean sales of 78.3 with a standard deviation of 8.5.
Let [tex]\mu_1[/tex] = mean sales per market in Region 1.
[tex]\mu_2[/tex] = mean sales per market in Region 2.
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu_1-\mu_2[/tex] = 0 {means that there is no difference in potential mean sales per market in Region 1 and 2}
Alternate Hypothesis, [tex]H_A[/tex] : > [tex]\mu_1-\mu_2\neq[/tex] 0 {means that there is a difference in potential mean sales per market in Region 1 and 2}
The test statistics that will be used here is Two-sample t-test statistics because we don't know about population standard deviations;
T.S. = [tex]\frac{(\bar X_1 -\bar X_2)-(\mu_1-\mu_2)}{s_p \times \sqrt{\frac{1}{n_1}+ {\frac{1}{n_2}}} }[/tex] ~ [tex]t__n_1_+_n_2_-_2[/tex]
where, [tex]\bar X_1[/tex] = sample mean sales in Region 1 = 84
[tex]\bar X_2[/tex] = sample mean sales in Region 2 = 78.3
[tex]s_1[/tex] = sample standard deviation of sales in Region 1 = 6.6
[tex]s_2[/tex] = sample standard deviation of sales in Region 2 = 8.5
[tex]n_1[/tex] = sample of supermarkets from Region 1 = 12
[tex]n_2[/tex] = sample of supermarkets from Region 2 = 17
Also, [tex]s_p=\sqrt{\frac{(n_1-1)\times s_1^{2}+(n_2-1)\times s_2^{2} }{n_1+n_2-2} }[/tex] = [tex]s_p=\sqrt{\frac{(12-1)\times 6.6^{2}+(17-1)\times 8.5^{2} }{12+17-2} }[/tex] = 7.782
So, the test statistics = [tex]\frac{(84-78.3)-(0)}{7.782 \times \sqrt{\frac{1}{12}+ {\frac{1}{17}}} }[/tex] ~ [tex]t_2_7[/tex]
= 1.943
The value of t-test statistics is 1.943.
Now, at a 0.02 level of significance, the t table gives a critical value of -2.472 and 2.473 at 27 degrees of freedom for the two-tailed test.
Since the value of our test statistics lies within the range of critical values of t, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region.
Therefore, we conclude that there is no difference in potential mean sales per market in Region 1 and 2.
Two samples from the same population both have M = 84 and s2 = 20, but one sample has n = 10 and the other has n = 20 scores. Both samples are used to evaluate a hypothesis stating that μ = 80 and to compute Cohen’s d. How will the outcomes for the two samples compare?
Complete Question
Two samples from the same population both have M = 84 and s2 = 20, but one sample has n = 10 and the other has n = 20 scores. Both samples are used to evaluate a hypothesis stating that μ = 80 and to compute Cohen’s d. How will the outcomes for the two samples compare?
a.
The larger sample is more likely to reject the hypothesis and will produce a larger value for Cohen’s d.
b.
The larger sample is more likely to reject the hypothesis, but the two samples will have the same value for Cohen’s d.
c.
The larger sample is less likely to reject the hypothesis and will produce a larger value for Cohen’s d.
d.
The larger sample is less likely to reject the hypothesis, but the two samples will have the same value for Cohen’s d.
Answer:
The Cohen's d value is [tex]d = 0.895[/tex]
The correct option is b
Step-by-step explanation:
From the question we are told that
The sample mean of each population is [tex]M = 84[/tex]
The variance of each population is [tex]s^2 = 20[/tex]
The first sample size is [tex]n_1 = 10[/tex]
The second sample size is [tex]n_2 = 20[/tex]
The null hypothesis is [tex]H_o : \mu = 80[/tex]
Generally the standard deviation is mathematically evaluated as
[tex]s = \sqrt{20 }[/tex]
=> [tex]s = 4.47[/tex]
The first test statistics is evaluated as
[tex]t_1 = \frac{M - \mu }{ \frac{\sigma }{ \sqrt{n_1} } }[/tex]
=> [tex]t_1 = \frac{84 - 80 }{ \frac{4.47 }{ \sqrt{10} } }[/tex]
=> [tex]t_1 = 2.8298[/tex]
The second test statistics is evaluated as
[tex]t_2 = \frac{M - \mu }{ \frac{\sigma }{ \sqrt{n_2} } }[/tex]
=> [tex]t_2 = \frac{84 - 80 }{ \frac{4.47 }{ \sqrt{20} } }[/tex]
=> [tex]t_2 = 4.0[/tex]
The sample with the larger test statistics (sample size) will more likely reject the null hypothesis
Generally the Cohen's d value is mathematically evaluated as
[tex]d = \frac{M - \mu }{s }[/tex]
=> [tex]d = \frac{ 84 - 80 }{4.47 }[/tex]
=> [tex]d = 0.895[/tex]
Given that the the sample mean and sample size are the same for both sample the Cohen's d value will be the same
i will give brainliest and 5 stars if you help ASAP
Find the value of the variable(s) in each figure. Explain your reasoning. Thank you in advance
Answer:
1. x 55
2. y 117
x 51
3.x39
y116
4.x 18
5.x 48
y 14
for the last one I'm not sure. please give 5 start
A truck carries 360 crates of avocados to a grocery distribution center. If there are 8640 avocados total, how many avocados are in each crate?
Answer:
There are 24 avocados in each crate.
Step-by-step explanation:
This is a division problem.
8640/360 = 24
There are 24 avocados in each crate.
coefficient of 8x+7y
Answer:
8
Step-by-step explanation:
Identify the exponents on the variables in each term, and add them together to find the degree of each term.
8x→1
7y→1
The largest exponent is the degree of the polynomial.
1
The leading term in a polynomial is the term with the highest degree.
8x
The leading coefficient of a polynomial is the coefficient of the leading term.
____________________________________________________________
The leading term in a polynomial is the term with the highest degree.
8x
The leading coefficient in a polynomial is the coefficient of the leading term.
8
List the results.
Polynomial Degree: 1
Leading Term: 8x
Leading Coefficient: 8
Hope This Helps!!!
Which represents a measure of volume?
O 5 cm
O 5 square cm
05 cm
05 cm
Answer:
5 cm³
Step-by-step explanation:
The correct options to the given question will be:
5 cm³ 5 square cm 5 cm 5 cm²The volume of a solid is referred to as the space that the figure occupies. The three dimensions are covered and recorded to measure the volume. It is measured by multiplying the length, breadth, and the height of the solid. Since three units are multiplies, therefore the unit of the volume becomes a cubic unit. Usually, the volume is measured in cubic meter or cubic centimetre.
Given the function f ( x ) = 2 x + 8 , evaluate and simplify the expressions below. See special instructions on how to enter your answers.
Answer:
[tex]f(a) = 2a + 8[/tex]
[tex]f(x + h) = 2x + 2h + 8[/tex]
[tex]\frac{f(x + h) - f(x)}{h} = 2[/tex]
Step-by-step explanation:
Given
[tex]f(x) = 2x + 8[/tex]
Required
[tex]f(a)[/tex]
[tex]f(x + h)[/tex]
[tex]\frac{f(x + h) - f(x)}{h}[/tex]
Solving for f(a)
Substitute a for x in the given parameter
[tex]f(x) = 2x + 8[/tex] becomes
[tex]f(a) = 2a + 8[/tex]
Solving for f(x+h)
Substitute x + h for x in the given parameter
[tex]f(x + h) = 2(x + h) + 8[/tex]
Open Bracket
[tex]f(x + h) = 2x + 2h + 8[/tex]
Solving for [tex]\frac{f(x + h) - f(x)}{h}[/tex]
Substitute 2x + 2h + 8 for f(x + h), 2x + 8 fof f(x)
[tex]\frac{f(x + h) - f(x)}{h}[/tex] becomes
[tex]\frac{2x + 2h + 8 - (2x + 8)}{h}[/tex]
Open Bracket
[tex]\frac{2x + 2h + 8 - 2x - 8}{h}[/tex]
Collect Like Terms
[tex]\frac{2x - 2x+ 2h + 8 - 8}{h}[/tex]
Evaluate the numerator
[tex]\frac{2h}{h}[/tex]
[tex]2[/tex]
Hence;
[tex]\frac{f(x + h) - f(x)}{h} = 2[/tex]
HELPP PLEASEE ��2222 is the diameter of a circle. The coordinates are �(−2, −3) and �(−12, −5). At what coordinate is the center of the circle located? A. (5, 1) B. (−5, −1) C. (−4, −7) D. (−7, −4)
Answer:
(-7, -4) which is your answer D in the list of options
Step-by-step explanation:
The center of the circle should be located half way in between the given points on the plane.
Then the center ahs to be located half way for the x coordinates of both points:
half way between -12 and -2 (notice that there is a difference of 10 units between them), therefore half way would be at 5 units to the right from the furthest point, that is -12 + 5 = -7
Similarly, for the y coordinate, we see that the difference is between -5 and -3 (a difference of two units) therefore the center point will be located half way (that is one unit) up from the lowest y coordinate: -5 + 1 = -4
Then the center of the circle is located at (-7, -4)
Question on Statistics and Confidence Intervals
A field test for a new exam was given to randomly selected seniors. The exams were graded, and the sample mean and sample standard deviation were calculated. Based on the results, the exam creator claims that on the same exam, nine times out of ten, seniors will have an average score within 5% of 75%.
Is the confidence interval at 90%, 95%, or 99%? What is the margin of error? Calculate the confidence interval and explain what it means in terms of the situation. (10 points)
The phrasing "nine times out of ten" means 9/10 = 0.90 = 90% is the confidence level. We're confident 90% of the time that the confidence interval captures the population parameter we're after (in this case mu = population mean)
The portion "have an average score within 5% of 75%" means that 75% = 0.75 is the center of the confidence interval, and it goes as low as 0.75 - 0.05 = 0.70 and as high as 0.75 + 0.05 = 0.80
This confidence interval is from 70% to 80%, meaning that nine times out of ten, we're confident that the average score is between 70% and 80%
We write the confidence interval as (0.70, 0.80). It's common to use the notation (L, U) to indicate the lower (L) and upper (U) boundaries. You might see the notation in the form L < mu < U. If so, then it would be 0.70 < mu < 0.80; either way they mean the same thing.
The margin of error is 0.05 as its the 5% radius of the interval. It tells us how far the most distant score is from the center (75%)
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In summary, we have these answers
confidence level = 90%margin of error = 5% = 0.05confidence interval = (0.70, 0.80)interpretation = We're 90% confident that the average exam score is between 0.70 and 0.80CD is the perpendicular bisector of XY Determine the value of x. Question 8 options: A) –2 B) –1∕2 C) 4 D) 1.25
Answer:
Step-by-step explanation:
12x - 9 = 8x + 7
4x - 9 = 7
4x = 16
x = 4
solution is C
The solution is Option C.
The value of x is given from the equation x = 4
What is perpendicular bisector?A perpendicular bisector is defined as a line or a line segment that divides a given line segment into two parts of equal measurement. Lines that cross each side's midpoint and are perpendicular to the specified side are known as a triangle's perpendicular bisectors.
The perpendicular bisector theorem states that any point on the perpendicular bisector is equidistant from both the endpoints of the line segment on which it is drawn
Given data ,
Let the first line be represented as CD
Let the second line be represented as XY
Now , CD is the perpendicular bisector of XY
So , the point F is the midpoint of the line segment XY
The measure of line segment XF = 12x - 9
The measure of line segment FY = 8x + 7
From the perpendicular bisector theorem ,
The measure of line segment XF = The measure of line segment FY
Substituting the values in the equation , we get
12x - 9 = 8x + 7
Subtracting 8x on both sides of the equation , we get
4x - 9 = 7
Adding 9 on both sides of the equation , we get
4x = 16
Divide by 4 on both sides of the equation , we get
x = 4
Therefore , the value of x = 4
Hence , the value of the equation is x = 4
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