Answer:
a) The Z-score for Patricia's test grade is 0.32.
b) The z-score for Whitney's test grade is of 0.34.
c) Due to the higher z-score, Whitney's did relatively better.
Step-by-step explanation:
Z-score:
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.
a. Calculate the Z-score for Patricia's test grade.
Patricia took a test in English and earned a 76.5. Students' test grades in the English class had a mean of 73.1 and a standard deviation of 10.5.
This means that [tex]X = 76.5, \mu = 73.1, \sigma = 10.5[/tex]
The z-score is:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{76.5 - 73.1}{10.5}[/tex]
[tex]Z = 0.32[/tex]
The Z-score for Patricia's test grade is 0.32.
b. Calculate the z-score for Whitney's test grade.
Whitney took a test in Math and earned a 64.5. Students' test grades in Math had a mean of 60.9 and a standard deviation of 10.7.
This means that [tex]X = 64.5, \mu = 60.9, \sigma = 10.7[/tex]
The z-score is:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{64.5 - 60.9}{10.7}[/tex]
[tex]Z = 0.34[/tex]
The z-score for Whitney's test grade is of 0.34.
c. Which person did relatively better?
Due to the higher z-score, Whitney's did relatively better.
From a group of 12 teachers, how many different committees can be formed
consisting four or five members?
Answer:
3=4÷12
3groups with 4 members (teachers)and we cannot make groups with 5 members
Find the value of the expression 4d ÷ c + 3 when c = 3 and d = 6
The value of the expression 4d ÷ c + 3 is 11.
What is Expression?A mathematical expression is a phrase that has a minimum of two numbers or variables and at least one mathematical operation. Let's examine the writing of expressions.
A mathematical operation such as subtraction, addition, multiplication, or division is used to combine terms into an expression.
Given:
4d ÷ c + 3
Now, for d= 6 and c= 3
we have
4d ÷ c + 3
= 4(6) / 3 + 3
= 4(2) + 3
= 8+ 3
= 11
Hence, the value of the expression is 11.
Learn more about expression here:
https://brainly.com/question/14083225
#SPJ2
what is the area of the triangle 16, 10, 8
Answer:
480
Step-by-step explanation:
(16x10x8) divided by 2 = 480
One of the authors and some statistician friends have an ongoing series of Euchre games that will stop when one of the two teams is deemed to be statistically significantly better than the other team. Euchre is a card game and each game results in a win for one team and a loss for the other. Only two teams are competing in this series, which we'l call team 1 and team 2.
Required:
a. Define the parameter of interest.
b. What are the null and alternative hypotheses if the goal is to determine if either team is statistically significantly better than the other at winning Euchre?
Answer:
Parameter of interest is the proportion of games won by a certain team.
H0 : p = 0.5
H1 : p ≠ 0.5
Step-by-step explanation:
Parameter refers to any statistical measure which is derived from the population data. Therefore, the parameter of interest in the scenario described above is the proportion of win or loss by a particular team. This could be either team A or team B.
Probability of either of either win or loss :
Proportion, p of win = 0.5
Null hypothesis ; H0 : p = 0.5
Alternative hypothesis ; H1 : p ≠ 0.5
Scores at a local high school on the American College Testing (ACT) college entrance exam follow the normal distribution with a mean of 18 and a standard deviation of 8. A guidance counselor takes a random sample of 20 students and calculates the mean score, x¯.
(a) Calculate the mean and standard deviation of the sampling distribution of x¯.
(b) Interpret the standard deviation from part (a).
(c) Find the probability that a sample of 20 students has a mean score of 19.5 or more.
Answer:
a) The mean is 18 and the standard deviation is 1.79.
b) The interpretation is that the standard deviation of the sample means of groups of 20 students will be of 1.79, which is the sample error, which is different from the population standard deviation.
c) 0.2005 = 20.05% probability that a sample of 20 students has a mean score of 19.5 or more.
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 estabilishes 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.
Mean of 18 and a standard deviation of 8.
This means that [tex]\mu = 18, \sigma = 8[/tex]
Sample of 20:
This means that [tex]n = 20, s = \frac{8}{\sqrt{20}} = 1.79[/tex]
(a) Calculate the mean and standard deviation of the sampling distribution of x¯.
By the Central Limit Theorem, the mean is 18 and the standard deviation is 1.79.
(b) Interpret the standard deviation from part (a).
The interpretation is that the standard deviation of the sample means of groups of 20 students will be of 1.79, which is the sample error, which is different from the population standard deviation.
(c) Find the probability that a sample of 20 students has a mean score of 19.5 or more.
This is 1 subtracted by the pvalue of Z when X = 19.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{19.5 - 18}{1.79}[/tex]
[tex]Z = 0.84[/tex]
[tex]Z = 0.84[/tex] has a pvalue of 0.7995
1 - 0.7995 = 0.2005
0.2005 = 20.05% probability that a sample of 20 students has a mean score of 19.5 or more.
subtract 8 from 10, then add n to the result
Answer:
(10-8) + n
Step-by-step explanation:
Good luck with your work!
Answer and Step-by-step explanation:
To subtract 8 from 10, it would look like this:
10 - 8.
Now, we add n to the result.
(10 - 8) + n
The question said not to simplify any part of this, so this is the expression.
(10 - 8) + n
#teamtrees #PAW (Plant And Water)
Question 1
10 pts
The vertices of a triangle are P(4,7), Q(-1,7) and R(4,-5). What is the
perimeter of triangle PQR?
Answer:
30
Step-by-step explanation:
This problem can be done without the Distance Formula (which is a way to find the distance between any two points in the plane).
The attached image shows the points and segments joining them.
PQ = 5 because the points are on the same horizontal line, and you can count spaces between them (or subtract x-coordinates: 4 - (-1) = 5).
PR = 12 because the points are on the same vertical line; count spaces or subtract y-coordinates, 7 - (-5) = 12.
The triangle is a right triangle, so the Pythagorean Theorem can be used to find the length of the hypotenuse.
[tex](\text{leg})^2+(\text{leg})^2=(\text{hypotenuse})^2[/tex]
[tex](QR)^2=5^2+12^2=25+144=169\\QR=\sqrt{169}=13[/tex]
The perimeter of the triangle is 5 + 12 + 13 = 30
Please help me thanks
Answer:
11/13
Step-by-step explanation:
4 out of the 26 marbles are blue, meaning that the rest of the 22 marbles are not blue. (26-4=22)
This means that out of the total 26, the chance of not picking a blue marble are 22/26=11/13
What is m<1
help thais would help
Answer:
it means it is less than one
GIVING BRAINLY need urgent help give evidence if you just answer for points you will be reported no biTLY LINKS
Answer:
1/5
Step-by-step explanation:
I hope this helps you
Answer:
1/5
Step-by-step explanation:
each X is divided by 5 to get the Y
Find the erea of the trapezoid.
show work for brainliest
Answer:
the area of the trapezoid is 32
Step-by-step explanation:
a (base)2
b (Base)6
h (height)8
Eric is a great skateboard fan. He visits a shop named SKATERS to
check some prices. At this shop you can buy a complete board. Or
you can buy a deck, a set of 4 wheels, a set of 2 trucks and a set of
hardware, and assemble your own board. The prices for the shop's
products are:
Answer:
minimum: 80 zeds
maximum: 137 zeds
Step-by-step explanation:
minimum price is where you choose all the cheapest options
lowest deck price is 40, lowest wheel set price is 14...
40+14+16+10
=40+30+10
=80
maximum price is where you choose all the most expensive options
highest deck is 65, highest price of wheels are 36, hardware 20
65+36+16+20
=65+72
=137
Consider the following sample regressions for the linear, the quadratic, and the cubic models along with their respective R2 and adjusted R2.
Linear Quadratic Cubic
Intercept 29.83 29.35 26.88
x −0.04 0.16 2.11
x2 NA −0.02 −0.38
x3 NA NA 0.02
R2 0.001 0.001 0.008
Adjusted R2 −0.026 −0.053 −0.075
a. Predict y for x = 1 and 2 with each of the estimated models.
b. Select the most appropriate model.
1. Linear model
2. Cubic model
3. Quadratic model
Answer:
Kindly check explanation
Step-by-step explanation:
From the given information :
Linear model : y = - 0.04x + 29.83
Quadratic model : y = - 0.02x² + 0.16x + 29.35
Cubic model : y = 0.02x³ - 0.38x² + 2.11x + 26.88
Predicted y value for X = 1 ; X = 2
Linear model :
y = - 0.04(1) + 29.83 = 29.79
y = - 0.04(2) + 29.83 = 29.75
Quadratic model :
X = 1
y = - 0.02(1)^2 + 0.16(1) + 29.35 = 29.49
X = 2
y = - 0.02(2)^2 + 0.16(2) + 29.35 = 29.59
Cubic model :
X = 1
y = 0.02(1)^3 - 0.38(1)^2 + 2.11(1) + 26.88 = 28.63
X = 2
y = 0.02(2)^3 - 0.38(2)^3 + 2.11(2) + 26.88 = 28.22
Based on the R² value of the models given :
Linear ; R² = 0.001 ; R = sqrt(0.001) = 0.0316
Quadratic ; R² = 0.001 ; R = sqrt(0.001) = 0.0316
Cubic ; R² = 0.008 ; R = sqrt(0.008) = 0.089
Hence, the model which best fits the data is Cubic model.
n 2019, approximately 97.4% of all the runners who started the Boston Marathon (in Boston, Massachusetts, USA) were able to complete the 42.2 km (26.2 mile) race. If 100 runners are chosen at random, find the probability that at least 5 of them did not finish the marathon
Answer:
0.1199 = 11.99% probability that at least 5 of them did not finish the marathon
Step-by-step explanation:
For each runner, there are only two possible outcomes. Either they finished the marathon, or they did not. The probability of a runner completing the marathon is independent of any other runner. This means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
97.4% finished:
This means that 100 - 97.4 = 2.6% = 0.026 did not finish, which means that [tex]p = 0.026[/tex]
100 runners are chosen at random
This means that [tex]n = 100[/tex]
Find the probability that at least 5 of them did not finish the marathon
This is:
[tex]P(X \geq 5) = 1 - P(X < 5)[/tex]
In which
[tex]P(X < 5) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4)[/tex]
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{100,0}.(0.026)^{0}.(0.974)^{100} = 0.0718[/tex]
[tex]P(X = 1) = C_{100,1}.(0.026)^{1}.(0.974)^{99} = 0.1916[/tex]
[tex]P(X = 2) = C_{100,2}.(0.026)^{2}.(0.974)^{98} = 0.2531[/tex]
[tex]P(X = 3) = C_{100,3}.(0.026)^{3}.(0.974)^{97} = 0.2207[/tex]
[tex]P(X = 4) = C_{100,4}.(0.026)^{4}.(0.974)^{96} = 0.1429[/tex]
[tex]P(X < 5) = P(X = 0) + P(X = 1) + P(X = 2) + P(X = 3) + P(X = 4) = 0.0718 + 0.1916 + 0.2531 + 0.2207 + 0.1429 = 0.8801[/tex]
[tex]P(X \geq 5) = 1 - P(X < 5) = 1 - 0.8801 = 0.1199[/tex]
0.1199 = 11.99% probability that at least 5 of them did not finish the marathon
Simplify each expression using the Order of Operations.
8-6 divided by 2+3 X 5
Answer:
8 - 6 ÷ 2 + 3 × 5
8 - 3 + 15
5 + 15
20
what is the height of the cone
Answer:
28
Yes Pog, You are Poggers
Can someone help me?
Answer:
x = 12 efg = 132
Step-by-step explanation:
Hi,
4x = 48
x = 12
Which means...
m < EFG is
4x
4 (12) = 48
m < EFG is 48 degrees
I hope this helps :)
My teacher asked me 7 x 1/5 of 19, and I got immediately stumped. My brain is mush today.
Answer:
No lol that seems very confusing but was it 26.6?
Answer: 26.6
Step-by-step explanation:
7 times 1/5= 7/5
7/5 times 19= 26.6
I hope ti helps and may God bless you! have a nice day, bye!
pasagot po please...........
Answer:
1) ASA
2) SAS
3) SAS
4) SAS
5) SSS
If there are 35 learners in this class, then determine the percentage of
learners who obtained a distinction (( > 80%).
Answer:
The question is an incomplete question
someone please answer this!!
Answer:
it 45
Step-by-step explanation:
u add 75 and 60 together which equals 135
then u subtract 135 from 180 and u get 45
2 5/6+ 3 2/5 in simplest form.
Answer:
17/6 + 17/5
Step-by-step explanation:
What is the slope of the line that passes through (5,4) and (7,10)?
A. 3
B. -3
C. 2
D. -2
Answer:
A. 3
Step-by-step explanation:
I just did it on a calculator and got it correct
Solve the simultaneous equations
2x - 3y = 12
3x + 4y = 1
What am I doing wrong here?
Answer:
3
Step-by-step explanation:
2×-3y = 12 ( multiply whit 4)
3x + 4y =1 (multiply whit 3 )
8x -12y =48
9X+ 12y = 3
if you add this equations
17X =51
X= 51 / 17
x=3
There's your answer buddy!
Which of the following could be points on the unit circle?
Answer:
A and D
Step-by-step explanation:
Unit circle is a circle described by the equation
x^2 + y^2 = 1
We can try each pair and check
A. [tex](\frac{6}{7})^2 + (\frac{\sqrt{13}}{7})^2 = \frac{36}{49} + \frac{13}{49} = \frac{49}{49} = 1[/tex]
B. [tex](\frac{4}{3})^2 + (\frac{4}{5})^2 > (\frac{4}{3})^2 > 1[/tex]
C. [tex](\frac{1}{3})^2 + (\frac{2}{3})^2 = \frac{1}{9} + \frac{4}{9} = \frac{5}{9} < 1[/tex]
D. [tex](\frac{5}{13})^2 + (\frac{12}{13})^2 = \frac{25}{169} + \frac{144}{169} = \frac{169}{169} = 1[/tex]
A mayoral candidate in a large metropolitan area has hired you to take a poll to determine the proportion of registered voters who plan to vote for him. He would like you to report a 95% confidence interval with a margin of error no more than 0.04. Whiat is the smallest sample size that will produce an interval with these specifications?
Answer:
The smallest sample size that will produce an interval with these specifications is 601.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
He would like you to report a 95% confidence interval with a margin of error no more than 0.04. What is the smallest sample size that will produce an interval with these specifications?
We have to find n for which M = 0.04.
We dont know the true proportion, so we use [tex]\pi = 0.5[/tex], which is when the smallest sample size needed will have it's largest value.
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
[tex]0.04 = 1.96\sqrt{\frac{0.5*0.5}{n}}[/tex]
[tex]0.04\sqrt{n} = 1.96*0.5[/tex]
[tex]\sqrt{n} = \frac{1.96*0.5}{0.04}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*0.5}{0.04})^2[/tex]
[tex]n = 600.25[/tex]
Rounding up
The smallest sample size that will produce an interval with these specifications is 601.
By increasing the down payment from 1,000 to 4,000, how does the total purchasing cost change?
Answer:
300%
Step-by-step explanation:
By increasing the down payment from 1,000 to 4,000, how does the total purchasing cost change?
If down payment is increased from 1000 to 4000
Icecrement = 4000-1000
Increment =3000
Percentage increase = 3000/1000×100
Percentage increase = 3000/10
Percentage increas=300%
How many triangles can be made with sides measuring 7 cm, 4 cm, and 5 cm
Answer:
One triangle
Step-by-step explanation:
Since the sum of the shorter two sides is greater than the larger side.
Solve for x using
cross multiplication.
X + 8
-
3x – 2
8
3
x = [?]
Answer:
x=70
Step-by-step explanation:
(x+8)*8=(3x-2)*3
8x+64=9x-6
x=70
I need help fast!!!
Please
Answer:
B
Step-by-step explanation: