Answer:
It is 7x-7
Step-by-step explanation:
You have to add the two expressions, not subtract them.
Answer:
no you need to add, it would be 7x - 7
Step-by-step explanation:
You need to look at the line...they gave you the measurement for PR, and the measurement for RS...and they want you to find PS
You need to add because both PR and RS come together to form PS
Two methods, A and B, are available for teaching Spanish. There is a 70% chance of successfully learning Spanish if method A is used, and a 85% chance of success if method B is used. However, method B is substantially more time consuming and is therefore used only 20% of the time (method A is used the other 80% of the time). The following notations are suggested:
A—Method A is used.
B—Method B is used.
L—Spanish was learned successfully. A person learned Spanish successfully.
What is the probability that he was taught by method A?
Answer:
0.7671 = 76.71% probability that he was taught by method A
Step-by-step explanation:
Conditional Probability
We use the conditional probability formula to solve this question. It is
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]
In which
P(B|A) is the probability of event B happening, given that A happened.
[tex]P(A \cap B)[/tex] is the probability of both A and B happening.
P(A) is the probability of A happening.
In this question:
Event A: Person learned Spanish successfully.
Event B: Method A was used.
Probability of a person learning Spanish successfully:
70% of 80%(using method A)
85% of 20%(using method B)
So
[tex]P(A) = 0.7*0.8 + 0.85*0.2 = 0.73[/tex]
Probability of a person learning Spanish successfully and using method A:
70% of 80%, so:
[tex]P(A \cap B) = 0.7*0.8 = 0.56[/tex]
What is the probability that he was taught by method A?
[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.56}{0.73} = 0.7671[/tex]
0.7671 = 76.71% probability that he was taught by method A
Jen recently rode her bicycle to visit her friend who lives 6 miles away. On her way there, her average speed was & miles per hour faster than on her way home. If jen
spent a total of 2 hours bicycling find the two rates.
Answer:
(1) +t+=+1.2+ hrs
Step-by-step explanation:
Can someone help me with this an my other work please?
The owner of a golf course wants to determine if his golf course is more difficult than the one his friend owns. He has 8 golfers play a round of 18 holes on his golf course and records their scores. Later that week, he has the same 8 golfers play a round of golf on his friend's course and records their scores again. The average difference in the scores (treated as the scores on his course - the scores on his friend's course) is 9.582 and the standard deviation of the differences is 15.9274. Calculate a 90% confidence interval to estimate the average difference in scores between the two courses.1) (13.73,-0.65).2) (-10.359,-4.021).3) (-9.259,-5.121).4) (-13.745,-0.635).5) (13.745, -0.635).
Answer:
The 90% confidence interval to estimate the average difference in scores between the two courses is (-1.088, 20.252).
Step-by-step explanation:
We have the standard deviation for the differences, 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 = 8 - 1 = 7
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 7 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.9}{2} = 0.95[/tex]. So we have T = 1.8946
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.8946\frac{15.9274}{\sqrt{8}} = 10.67[/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 9.582 - 10.67 = -1.088
The upper end of the interval is the sample mean added to M. So it is 9.582 + 10.67 = 20.252
The 90% confidence interval to estimate the average difference in scores between the two courses is (-1.088, 20.252).
(S
Sue can shovel snow from her driveway in 65 minutes. Tom can do the same job in 45 minutes How long would a
take Sue and Tom to shovel the driveway if they worked together?
Answer:
26.59 minutes
Step-by-step explanation:
Let's say the time needed to do the driveway combined is x. Sue does y parts of the driveway, and Tom does z parts of the driveway. Combined, y + z = 100% = 1, as they finish the whole driveway.
Next, Tom will take 45 * z minutes to do his part of the driveway. For example, if he did 50% = 0.5 of the driveway, he would take 45 * 0.5 = 22.5 minutes to do it. Similarly, Sue will take 65 *y minutes to do her part of the driveway. Since they will finish at the same time, we can say
45 * z = 65 * y
y + z = 1
Therefore, if we subtract y from both sides of the second equation, we have
z = 1-y
We can then plug 1-y in for z in the first equation to get
45 * (1-y) = 65 * y
45 - 45*y = 65*y
add both sides by 45 * y to separate the y values and their coefficients
45 = 110 * y
divide both sides by 110 to find y
y = 45/110 = 0.409
Use 1-y=z to get z = 1-0.409 = 0.59
Therefore, 45*z = 26.59 = 65*y
uppose that the walking step lengths of adult males are normally distributed with a mean of 2.8 feet and a standard deviation of 0.2 feet. A sample of 76 men’s step lengths is taken. Step 1 of 2 : Find the probability that an individual man’s step length is less than 2.5 feet. Round your answer to 4 decimal places, if necessary.
Answer:
.0668
Step-by-step explanation:
Formula:
z=(x-average)/standard deviation
(2.5-2.8)/.2= -1.5
Go to a ztable and find the value for 1.5 (.9332) and take the compliment of this (we can do this because the normal distribution is symmetrical)
1-.9332= .0668
help me please i am struggle with this
In a random sample of 26 residents of the state of Montana, the mean waste recycled per person per day was 2.8 pounds with a standard deviation of 0.23 pounds. Determine the 80% confidence interval for the mean waste recycled per person per day for the population of Montana. Assume the population is approximately normal. Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The critical value that should be used in constructing the confidence interval is T = 1.316.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
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 = 26 - 1 = 25
80% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 25 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.8}{2} = 0.9[/tex]. So we have T = 1.316
The critical value that should be used in constructing the confidence interval is T = 1.316.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 1.316\frac{0.23}{\sqrt{26}} = 0.059[/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 2.8 - 0.059 = 2.741 pounds
The upper end of the interval is the sample mean added to M. So it is 2.8 + 0.059 = 2.859 pounds.
The 80% confidence interval for the mean waste recycled per person per day for the population of Montana is between 2.741 pounds and 2.859 pounds.
For this problem I believe the answer is option A, B and C. But just wanted to confirm. Is that correct or is my answer wrong?
Answer:
Just A and C
Step-by-step explanation:
B doesn't count because you would not be looking at the 9. Only the 4.
You only look at one number to the right.
Answer:
A and C are correct, but not B
Step-by-step explanation:
When you round, you only look at the number behind the place you are rounding.
6.04 doesn't round to 6.1, so that is not correct
The alternative hypothesis for a two-tailed test of a single population proportion might be?
A. Ha: P>0.4
B. Ha: P< 0.4
C. Ha: p~=0.4 (~means not equal to)
Answer:
tgis moght help
Step-by-step explanation:
https://opentextbc.ca/introbusinessstatopenstax/chapter/full-hypothesis-test-examples/
evaluate the expression when b=3
y = -7
4b-y
Answer:
5
Step-by-step explanation:
Given :
b = 3 y = -7To Find :
Value of 4b - y .Solution:
Put on the respective values ,
⇒ 4b - y = 4 × 3 - 7
⇒ 4b - y = 12 - 7
⇒ 4b - y = 5
Hence the required answer is 5 .
Answer: 5
Step-by-step explanation:
We can plug in the numbers for variables. So, our new equation would becomes 4x3-7. We first evaluate 4x3=12. Then, 12-7=5. Hence, your answer is 5.
Find the angle between the vectors ????=????+???? and ????=−????+????. (Give an exact answer. Use symbolic notation and fractions where needed.)
Answer:
The angle between them is 60 degrees
Step-by-step explanation:
Given
[tex]a = 2i + j -3k[/tex]
[tex]b = 3i - 2j -k[/tex]
Required
The angle between them
The cosine of the angle between them is:
[tex]\cos(\theta) = \frac{a\cdot b}{|a|\cdot |b|}[/tex]
First, calculate a.b
[tex]a \cdot b =(2i + j -3k) \cdot (3i - 2j -k)[/tex]
Multiply the coefficients of like terms
[tex]a \cdot b =2 * 3 - 1 * 2 - 3 * -1[/tex]
[tex]a \cdot b =7[/tex]
Next, calculate |a| and |b|
[tex]|a| = \sqrt{2^2 + 1^2 + (-3)^2[/tex]
[tex]|a| = \sqrt{14[/tex]
[tex]|b| = \sqrt{3^2 + (-2)^2 + (-1)^2}[/tex]
[tex]|b| = \sqrt{14}[/tex]
Recall that:
[tex]\cos(\theta) = \frac{a\cdot b}{|a|\cdot |b|}[/tex]
This gives:
[tex]\cos(\theta) = \frac{7}{\sqrt{14} * \sqrt{14}}[/tex]
[tex]\cos(\theta) = \frac{7}{14}[/tex]
[tex]\cos(\theta) = 0.5[/tex]
Take arccos of both sides
[tex]\theta =\cos^{-1}(0.5)[/tex]
[tex]\theta =60^o[/tex]
Which expression is equivalent to the difference shown?
Answer:
Option A. -1/20x
Step-by-step explanation:
[tex] \frac{5x + 1}{5x} - \frac{4x + 1}{4x} [/tex]
[tex] = \frac{20x + 4x - 20x - 5x}{20x^{2} } [/tex]
[tex] = \frac{ - x}{20x^{2} } [/tex]
[tex] - \frac{1}{20x} [/tex]
Answered by GAUTHMATH
Given the function
Calculate the following values:
Answer:
f(-1) = 1
f(0) = 20
f(2) = 38
Step-by-step explanation:
f(-1) = 9×-1 + 10 = -9 + 10 = 1
f(0) = 9×0 + 20 = 0 + 20 = 20
f(2) = 9×2 + 20 = 18 + 20 = 38
we needed to use the second definition for f(0), because that is the same as saying x=0.
and that is in the domain of the second function definition ( x>=0).
If f(x) is a linear function, what is the value of n?
х
_4
f(x)
---25
-10
-1
n
20
2
оооо
9
Step-by-step explanation:
You can simply plot these points on a graph and see where the line goes. It go
The triangles are similar by??
the SAS similarity theorem
Which point is on the line y=-2x+ 3?
(-2, -1)
( 3, -3)
(3, 3)
(-3, -9)
please give how you got your answer
Answer: (3, -3)
Step-by-step explanation:
You substitute each point into the function and see if it fits:
(-2, -1) ⇒ -2(-2) + 3 = 4 + 3 = 7 ≠ -1
(3, -3) ⇒ -2(3) + 3 = -6 + 3 = -3
(3, 3) ⇒ -2(3) + 3 = -6 + 3 = -3 ≠ 3
(-3, -9) ⇒ -2(-3) + 3 = 6 + 3 = 9 ≠ -9
5x+2y=-3;x+5y=4
plz answer me
Answer:
x = -1 and y = 1
Step-by-step explanation:
5x + 2y = -3 . . . . . . . (i)
x + 5y = 4 . . . . . . . (ii)
Finding x in terms of y from eq. (ii) :-x + 5y = 4
x = 4 - 5y
Placing this value of x in eq. (i) :-5(4 - 5y) + 2y = -3
20 - 25y + 2y = -3
-23y = - 23
y = 1
Placing the value of y in eq. (i)5x + 2(1) = -3
5x + 2 = -3
5x = - 5
x = -1
The following data was collected from a survey in which people identified their average salaries over the past ten years. Identify the number of classes in the histogram.
Answer:
nine 9 classes in the histogram
The weights for newborn babies is approximately normally distributed with a mean of 5.4 pounds and a standard deviation of 1.8 pounds. Consider a group of 1500 newborn babies: 1. How many would you expect to weigh between 3 and 6 pounds
Answer:
You would expect 807 babies to weigh between 3 and 6 pounds.
Step-by-step explanation:
We are given that
Mean,[tex]\mu=5.4[/tex]pounds
Standard deviation,[tex]\sigma=1.8[/tex]pounds
n=1500
We have to find how many would you expect to weigh between 3 and 6 pounds.
The weights for newborn babies is approximately normally distributed.
Now,
[tex]P(3<x<6)=P(\frac{3-5.4}{1.8}<\frac{x-\mu}{\sigma}<\frac{6-5.4}{1.8})[/tex]
[tex]=P(-1.33<Z<0.33)[/tex]
[tex]P(3<x<6)=P(Z<0.33)-P(Z<-1.33)[/tex]
[tex]P(3<x<6)=0.62930-0.09176[/tex]
[tex]P(3<x<6)=0.538[/tex]
Number of newborn babies expect to weigh between 3 and 6 pounds
=[tex]1500\times 0.538=807[/tex]
Althea has $100. She divides it evenly among her 4 children. Her oldest child, Raul, spends $15 of the amount he receives. How much money does Raul have left after he spends $15?
Which statements about this word problem are true? Check all that apply.
This is an example of a part-whole problem.
This is an example of a comparison problem.
Addition then multiplication can be used to solve the problem.
Division then subtraction can be used to solve the problem.
Division then multiplication can be used to solve the problem.
Step-by-step explanation:
she gives each of her children $25 each,if Raul spends $15 then he would have $10 left.
Division then subtraction can be used to solve the problem.
What is mathematical expressions?An expression in mathematics is made up of numbers, variables, and functions (such as addition, subtraction, multiplication or division etc.) You can think of expressions as being comparable to phrases.
Given
she gives each of her children $25 each,if Raul spends $15 then he would have $10 left.
to learn more about mathematical expressions refer to:
https://brainly.com/question/14712183
#SPJ2
What is the value of b?
Answer:
?
Step-by-step explanation:
Larry deposits $15 a week into a savings account. His balance in his savings account grows by a constant percent rate.
True
False
Answer:
The answer is true
Step-by-step explanation:
3.
Salary: A sales clerk receives a monthly
salary of $500 plus a commission of 6% on all
sales over $3500. What did the clerk earn the
month she sold $8000 in merchandise?
Answer:
Step-by-step explanation:
I might be wrong but it 1900 in merchandise
The clerk earned a total of $770 for the month she sold $8000 in merchandise.
To calculate the clerk's earnings for the month she sold $8000 in merchandise, we need to consider her monthly salary and commission.
The clerk's monthly salary is $500, which is a fixed amount.
For the commission, we need to calculate the sales amount that exceeds $3500. In this case, the sales amount exceeding $3500 is $8000 - $3500 = $4500.
The commission is calculated as 6% of the sales amount exceeding $3500. Therefore, the commission earned by the clerk is 6% of $4500.
Commission = 6/100 * $4500
Commission = $270
Adding the monthly salary and commission, we can calculate the clerk's total earnings for the month:
Total earnings = Monthly salary + Commission
Total earnings = $500 + $270
Total earnings = $770
Therefore, the clerk earned a total of $770 for the month she sold $8000 in merchandise.
To know more about merchandise. here
https://brainly.com/question/27046371
#SPJ2
In the coordinate plane, two vertices of square ABCD are A (0,0) and B (0, m). What are the coordinates of points C and D? Do not introduce any new variables.
Answer:
Step-by-step explanation:
As shown in the graph,
A, B, C and D are the vertices of a square, all sides of the square will be equal in measure.
Coordinates of A → (0, 0)
Coordinates of B → (0, m)
Distance between point D and point A = m
Therefore, coordinates of point D → (m, 0)
Now point C will be equally distant from the points B and D.
Coordinates of C → (m, m)
if the mean of a random variable X is 45 what will be the mean of the sampling distribution of the sample mean?
Answer:
The mean of the sampling distribution is always equal to the mean of the population.
The mean of the sampling distribution of the sample mean is 45.
Given that,
The mean of the random variable X is 45.We need to find out the mean of the sampling distribution.Based on the above information, the calculation is as follows:
= mean of the random variable X
= 45
As the sampling distribution mean should always be equivalent to the population mean.
Therefore we can conclude that the mean of the sampling distribution of the sample mean is 45.
Learn more: brainly.com/question/521501
Find the appropriate answer for each word problem.
a. A group of twelve art students are visiting a local art museum for a field trip. The total cost of admission for the students is $125. What is the cost of admission for each student?
b. The school van can carry twelve passengers at a time. What is the least number of trips the van must make in order to bring 125 passengers to the same location?
c. Charlotte and her mother baked 125 cookies to give as Christmas gifts to their neighbors. If they plan to give a dozen cookies to each neighbor, how many neighbors will receive a gift?
d. Nicholas and Elaine are planning to serve cheesecake for dessert at their wedding and have purchased twelve cheesecakes. If the cheesecakes are divided evenly among the 125 wedding guests, how much cheesecake will each guest receive?
I WILL GIVE BRAINLIEST IF CORRECT
Answer:
a. $10
b. 10.46
c. 10.46
d. 0.096
A paper weight is made in the shape of a triangular pyramid.The dimensions of the paper weight are shown The formula for the volume of a triangular pyramid is V = 1/3 Bh .Which expression can be usef to find the value of B the area of the base of the pyramid
Answer:
[tex]B = \frac{3V}{h}[/tex]
Step-by-step explanation:
Given
[tex]V = \frac{1}{3}Bh[/tex]
Required
Solve for B
We have;
[tex]V = \frac{1}{3}Bh[/tex]
Multiply by 3
[tex]3V = Bh[/tex]
Make B the subject
[tex]B = \frac{3V}{h}[/tex]
Chloe has a small dog and a large dog. Each day, the small dog eats 3/4 cup of dog food, and the large dog 2 1/2 cups of dog food. In one week, how much more dog food does the large dog eat than the small dog ?
A. 1 3/4 cups
B. 8 3/4 cups
C. 12 1/4 cups
D. 22 3/4 cups
Answer:
A
Step-by-step explanation:
small dog eats 3/4 cup each day
large dog eats 1 cup each day
~after 1 week (x7)~
small dog = 5.25 cups
large dog = 7 cups
(7-5.25=1.75)
= therefore 1 and 3/4 cups
help me pleaseeeeeeeeeeeeeeeeee………….
Answer:
C
Step-by-step explanation:
200 x 5 = 1,000
100 x 10 = 1,000
C - 5 to 10 days
Answer:
C. 5 to 10 days
Step-by-step explanation:
If she drove 100 miles per day, then
1000/100 = 10
it took her 10 days.
If she drove 200 miles per day, then
1000/200 = 5
it took her 5 days.
Since she drove between 100 miles and 200 miles per days,
it took her from 5 to 10 days.
Answer: C. 5 to 10 days