Answer:
R = 0.862
Strong positive relationship
Step-by-step explanation:
Given the data:
Test Chemistry Student Score,
x Grade, y
1 2 3 4 5 6 7 8 9 10 11 12
Score,x = 65 50 55 65 55 70 65 70 55 70 50 55
Grade, y = 85 74 76 90 85 87 94 98 81 91 76 74
Using technology :
The CORREL function in excel, calculators will give accurate value of the correlation Coefficient between two variables, x and y. The correlation Coefficient obtained using technology is : 0.862
The correlation Coefficient value ranges between (-1 and 1) with values closer to either - 1 or 1 reflecting stronger relationship. A value of 0 means there is no relationship between the variables. Negative values indicate negative relationships while positive indicates positive association between the variables.
Therefore. With a correlation Coefficient of 0.862, the correlation Coefficient can be interpreted as meaning that ; there is a strong positive relationship between score and grade.
All of the following are equivalent except
x-7
X-(-7)
-7+x
x+(-7)
Answer:
X-(-7)
Step-by-step explanation:
If you are subtract by a negative number it turns it into a positive. It would look like this: X+(+7)
Suppose that a category of world-class runners are known to run a marathon in an average of 147 minutes with a standard deviation of 12 minutes. Consider 49 of the races. Find the probability that the runner will average between 146 and 150 minutes in these 49 marathons. (Round your answer to two decimal places.)
Answer:
0.6524 = 65.24% probability that the runner will average between 146 and 150 minutes in these 49 marathons.
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.
Average of 147 minutes with a standard deviation of 12 minutes.
This means that [tex]\mu = 147, \sigma = 12[/tex]
Consider 49 of the races.
This means that [tex]n = 49, s = \frac{12}{\sqrt{49}} = \frac{12}{7} = 1.7143[/tex]
Find the probability that the runner will average between 146 and 150 minutes in these 49 marathons.
This is the p-value of Z when X = 150 subtracted by the p-value of Z when X = 146. So
X = 150
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{150 - 147}{1.7143}[/tex]
[tex]Z = 1.75[/tex]
[tex]Z = 1.75[/tex] has a p-value of 0.9599
X = 146
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{146 - 147}{1.7143}[/tex]
[tex]Z = -0.583[/tex]
[tex]Z = -0.583[/tex] has a p-value of 0.3075.
0.9599 - 0.3075 = 0.6524.
0.6524 = 65.24% probability that the runner will average between 146 and 150 minutes in these 49 marathons.
Lines a and b are perpendicular. If the slope of line a is 3, what is the slope of
line b?
Answer:
-1/3
Step-by-step explanation:
Perpendicular lines have slopes that multiply to -1
a*b = -1
3 * b = -1
b = -1/3
The slope of line b is -1/3
Assuming boys and girls are equally likely, find the probability of a couple having a baby boy when their third child is born, given that the first two children were both boys
The required probability of a couple having a baby boy when their third child is born is 1/2.
What is probability?probability is the ratio of the number of favorable outcomes and the total number of possible outcomes. The chance that a particular event (or set of events) will occur expressed on a linear scale from 0 (impossibility) to 1 (certainty), also expressed as a percentage between 0 and 100%.
Given:
Assuming boys and girls are equally likely.
The first two children were both boys
According to given question we have
The probability of having a baby girl is an independent probability.
The first two children were both boys
So, it is not related to the previous child.
So required probability = 1/2
Therefore, the required probability of a couple having a baby boy when their third child is born is 1/2.
Learn more details about probability here:
https://brainly.com/question/11234923
#SPJ2
A runner can run 2 miles in 14 minutes. At this rate, how many miles can he run in 70 minutes?
Answer:
The answer is that the runner can run 10 miles in 70 minutes.
Step-by-step explanation:
To solve for the number of miles that the runner can run in 70 minutes, start by setting up the information given from the problem in the form of a proportion.
A proportion is an equation which defines that the two given ratios are equivalent to each other. In other words, the proportion states the equality of the two fractions or the ratios. In a proportion, if two sets of given numbers are increasing or decreasing in the same ratio, then the ratios are said to be directly proportional to each other.
The proportion for this problem will look like [tex]\frac{2 miles}{14 minutes}=\frac{x}{70 minutes}[/tex]. (x) will be used as the variable for the number of miles that the runner can run in 70 minutes.
To solve the proportion, start by cross multiplying to form an equation, and the equation will look like [tex](14)(x)=(2)(70)[/tex]. Next, simplify the equation, which will look like [tex](14)(x)=140[/tex]. Then, solve the equation by dividing both sides of the equation by 14, and it will look like [tex]x=10[/tex]. The final answer is that the runner can run 10 miles in 70 minutes.
How many numbers multiple of 3 are in the range [2,2000]?
Answer:
There are 666 numbers multiple of 3 in the interval.
Step-by-step explanation:
Multiples of 3:
A number is a multiple of 3 if the sum of it's digits is a multiple of 3.
Range [2,2000]:
First multiple of 3 in the interval: 3
Last: 1998
How many:
[tex]1 + \frac{1998 - 3}{3} = 1 + 665 = 666[/tex]
There are 666 numbers multiple of 3 in the interval.
A triangle has base of 7 1/8 feet and height 6 1/4 feet. Find the area of a triangle as a mixed number.
Answer: The area is 22 17/64.
Step-by-step explanation:
base = 7 1/8 = 57/8
height = 6 1/4 = 25/4
area = 1/2*b*h
= 1/2*57/8*25/4
= 1425/64
= 22 17/64
6.(a) A laptop was bought at Canadian $ 770. If the tax of 20% and 13% VAT should be paid, find the least selling price of it in Nepali rupee that prevents the shopkeeper from loss?
The LEAST selling price of the laptop should be ;
$1024.1 in other to avoid loss.
Price of laptop = $770
Tax = 20%
VAT = 13%
TO avoid loss ;
both the VAT percentage and TAX must be added to the price of the laptop:
Total percentage = VAT + TAX = (20 + 13) = 33%
THEREFORE, Least selling price should be :
Price of laptop * (1 + 33%)
770 * 1.33
= $1024.1
Learn more about TAX :
https://brainly.in/question/31818297
1% defective parts. 100,00 parts made in total. The number of defects made should equal?
Answer:
1,000 defects
Step-by-step explanation:
Find how many defects that should be made by finding 1% of 100,000:
100,000(0.01)
= 1000
So, there should be 1,000 defects
Question 4 of 16
If the probability of rain today is 35%, what is the probability that it will not rain
today?
A. 100%
B. 65%
C. 35%
D. 50%
Answer:
I think the answer is B. 65%
Probability of picking a blue marble and a yellow marble when 2 marbles are picked (without replacement) from a bag containing 4 blue and 4 yellow marbles
Answer:
9/49
Step-by-step explanation:
that is the procedure above
PLEASE HELP!!!!!!!!! DUE ASAP I WILL GIVE BRAINLIEST!!!!!!!!
Explanation:
A = values on the die greater than 1
A = {2,3,4,5,6}
B = values on the die less than 5
B = {1,2,3,4}
Union those two sets together
C = A u B = {1,2,3,4,5,6}
Effectively, we get every possible value on the die. This is due to the "or" keyword. If it was "and", then it would be a difference story.
So the probability of getting anything in set C is 100% or just 1. We have guaranteed certainty we'll have this event happen.
Please how do I solve this.
Answer:
Horizontal Shift: Right 1
Vertical Shift: Down 5
Reflection: None
Explanation: To find the transformation, compare the function to the parent function (being in this case g(x)=1/x) and check to see if there is a horizontal or vertical shift or a reflection.
So, the answer would be Right 1, and down 5
Hope this helps you out :)
Suppose you believe that the true average daily trade volume for General Electric stock is 49,829,719 shares and a standard deviation of 21,059,637 shares. Considering a 95% confidence level: What is the minimum required sample size if you would like your sampling error to be limited to 1,000,000 shares
Answer:
The minimum sample size is 1,704.
Step-by-step explanation:
We have to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a p-value of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Standard deviation of 21,059,637 shares
This means that [tex]\sigma = 21059637[/tex]
What is the minimum required sample size if you would like your sampling error to be limited to 1,000,000 shares?
This is n for which [tex]M = 1000000[/tex], so:
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]1000000 = 1.96\frac{21059637}{\sqrt{n}}[/tex]
[tex]1000000\sqrt{n} = 1.96*21059637[/tex]
[tex]\sqrt{n} = \frac{1.96*21059637}{1000000}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*21059637}{1000000})^2[/tex]
[tex]n = 1703.8[/tex]
Rounding up:
The minimum sample size is 1,704.
given the recursive formula below, what are the first four terms of the sequence
Answer:
c
Step-by-step explanation:
The first four terms are 17, 15, 13, and 11.
What is a function?A function is a relationship between inputs where each input is related to exactly one output.
Example:
f(x) = 2x + 1
f(1) = 2 + 1 = 3
f(2) = 2 x 2 + 1 = 4 + 1 = 5
The outputs of the functions are 3 and 5
The inputs of the function are 1 and 2.
We have,
f(n):
f(1) = 17
f(n) = f(n - 1) - 2 if n > 1
Now,
The first term is 17.
The second term.
f(2) = f(2 - 1) - 2
= f(1) - 2
= 17 - 2
= 15
The third term.
= f(3 - 1) - 2
= f(2) - 2
= 15 - 2
= 13
The fourth term.
f(4) = f(4 - 1) - 2
= f(3) - 2
= 13 - 2
= 11
Thus,
The terms are 17, 15, 13, 11
Learn more about functions here:
https://brainly.com/question/28533782
#SPJ2
Suppose that there are two internet service providers in Kabwe, Eyeconnect and Topconnect.
Currently, Eyeconnect has 180 000 customers and Topconnect has 120 000 customers.
Assume that, every year, 10% of the customer base of Eyeconnect switches to Topconnect
and 5% of the customer base of Topconnect switches to Eyeconnect. For the purposes of this
question, suppose no customer leaves a company without switching to the other one and no
company attracts customers that are not leaving the other (that is, the only changes in
customer base come from switching between the two companies).
a. Find the number of customers of Eyeconnect and Topconnect after one year.
b. Find the number of customers of Eyeconnect after many years.
Answer:
a. 168000 for Eyeconnect, 132000 for Topconnect
b. 100,000
Step-by-step explanation:
a.
Because the change in customers are only due to leaving companies, we can say that, after one year, Eyeconnect loses 10% of its customers to Topconnect and Topconnect loses 5% of its customers to Eyeconnect. This represents all changes in customers.
First, we can calculate how much Eyeconnect loses, which is 10% of 180,000 = 0.1 * 180,000 = 18,000 . They then have 180,000 - 18,000 = 162,000 employees
Next, Topconnect loses 120,000 * 5% = 120,000 * 0.05 = 6,000. They then have 120,000-6,000 = 114,000 employees
We can then add the customer amounts. Note that we are subtracting both sides before adding as both companies gain and lose customers simultaneously.
We can then add how much one company lost to the other company's customers.
Eyeconnect gains 6,000 customers, so they then have 162,000 + 6,000 = 168000 employees. Topconnect gains 18,000 customers so they then have 114,000 + 18,000 = 132,000 employees
b.
After many years, the number of customers Eyeconnect has will be less than the number of customers that Topconnect has. One way to find the end amount of customers that Eyeconnect has is to figure out when the customer bases even out, or when Eyeconnect loses the same amount of customers as Topconnect so the customer base stays the exact same. We know that no customers leave or join the companies except to leave/join the other, so the total amount of customers between the two companies stays the exact same. The amount of customers is 180,000 + 120,000 = 300,000. Therefore, at the end amount,
Eyeconnect customers (E) + Topconnect customers (T) =300,000
Furthermore, if the amount of customers that leave Eyeconnect is the same that leaves Topconnect, we can say
E * 0.1 = T * 0.05
divide both sides by 0.05 to isolate the T
E * 0.1 / 0.05 = T
2 * E = T
plug that into the first equation
E + 2 * E = 300,000
3 * E = 300,000
divide both sides by 3 to isolate E
E = 100,000 after many years
Max has 3 fiction books and 6 nonfiction books to donate to the community center. He wants to package them so that there is an equal number of fiction and nonfiction books in each group. He also wants to have as many packages as possible. How many books are in each group?
Answer:
Each group has 1 fiction book and 2 nonfiction book(s).
Ellicott City Manufacturers, Inc., has sales of $6,344,210, and a gross profit margin of 67.3 percent. What is the firm's cost of goods sold? Round your final answer to the nearest dollar.
Answer:
$3792116
Step-by-step explanation:
that's the answer above
m∠AFD=90° . m∠AFB=31°. Find m∠DFE.
A. 87
B. 29.5
C. 31
D. 28
Answer:
D. 28
Step-by-step explanation:
Given:
m∠AFD = 90°
m∠AFB = 31°
Required:
m∠DFE
Solution:
m<AFB = m<CFD (both angles are marked as congruent angles)
Since m<AFB = 31°, therefore,
m<CFD = 31°
m<AFB + m<CFD + m<BFC = m<AFD
Plug in the known values
31° + 31° + m<BFC = 90°
62° + m<BFC = 90°
Subtract 62° from each side
m<BFC = 90° - 62°
m<BFC = 28°
m<BFC = m<DFE = 28° (both angles are marked congruent to each other)
Therefore,
m<DFE = 28°
Which points are also part of this set of equivalent ratios? Select all that apply.
a. (3, 2)
b. (4, 2)
c. (4, 8)
d. (8, 4)
e. (12, 6)
Answer:
Option b, (4,2)
Option d, (8,4)
Option e, (12,6)
Answered by GAUTHMATH
Answer:
Option b, (4,2)
Option d, (8,4)
Option e, (12,6)
Step-by-step explanation:
the person above me is correct
I need some help please!!!
9514 1404 393
Answer:
13 < √181 < 14
Step-by-step explanation:
Apparently, you're supposed to know that ...
13² = 169
14² = 196
so √181 will lie between 13 and 14.
13 < √181 < 14
The lines shown below are parallel. If the green line has a slope of 5, what is a
the slope of the red line?
Answer:
A. 5
Step-by-step explanation:
Parallel lines have the same slope.
Answer:
5
Step-by-step explanation:
Instructions: Find the missing length indicated.
Answer:
x = 65
Step-by-step explanation:
x = √(25×(25+144))
x = √(25×169)
x = 5×13
x = 65
Answered by GAUTHMATH
A sample of 4 children was drawn from a population of rural Indian children aged 12 to 60 months. The sample mean of mid-upper arm circumference was 150 mm with a standard deviation of 6.73. What is a 95% confidence interval for the mean of mid-upper arm circumference based on your sample
Answer:
The 95% confidence interval for the mean of mid-upper arm circumference based on your sample is between 139.29 mm and 160.71 mm.
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,which is the sample size subtracted by 1. So
df = 4 - 1 = 3
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 3 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 3.1824
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 3.1824\frac{6.73}{\sqrt{4}} = 10.71[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 150 - 10.71 = 139.29 mm
The upper end of the interval is the sample mean added to M. So it is 150 + 10.71 = 160.71 mm
The 95% confidence interval for the mean of mid-upper arm circumference based on your sample is between 139.29 mm and 160.71 mm.
Last question I need help on
( x + 1 )( x )( x - 5 ) =
( x + 1 )( x - 5 )( x ) =
( x^2 - 4x - 5 )( x ) =
x^3 - 4x^2 - 5x
Step-by-step explanation:
the other answer is basically correct.
as the simplest form you create 3 terms for the three given solutions (= the values for when the equation equals 0).
but maybe you need to add " = 0" for the full equation.
Make x the subject
5y + 2x = 25
Answer:
x = -5/2 y +25/2
Step-by-step explanation:
5y + 2x = 25
Subtract 5y from each side
5y + 2x -5y= -5y+25
2x = -5y +25
Divide by 2
2x/2 = -5y/2 +25/2
x = -5/2 y +25/2
A cyclist rides his bike at a speed of 15 miles per hour. What is this speed in kilometers per hour? How many kilometers will the cyclist travel in 4 hours? In your computations, assume that 1 mile is equal to 1.6 kilometers. Do not round your answers.
Answer:
Step-by-step explanation:
Speed = (15 mi)/hr × (1.6 km)/mi = (24 km)/hr
:::::
(4 hr) × (24 km)/hr = 96 km
What is the area of the polygon given below?
Answer:
diện tích đa giác trong hình là :
186 cm2
Step-by-step explanation:
hãy tách hình đa giác trên thành 4 hình chữ nhật và tính diện tích từng hình chữ nhật
What's the next number in the sequence 16, 4, 1,
Answer:
0.25
Step-by-step explanation:
16/4 = 4
4/4 = 1
1/4 = 0.25
0.25/4 = 0.0625
0.0625/4 = 0.015625
give me brainliest please:)
Solve for f(-7) plz thanks
Answer:
12
Step-by-step explanation:
If f(x) = 5 - x
Then f(-7) = 5 - (-7)
f(-7) = 5 + 7
f(-7) = 12
