An SAT prep course claims to improve the test score of students. The table below shows the scores for seven students the first two times they took the verbal SAT. Before taking the SAT for the second time, each student took a course to try to improve his or her verbal SAT scores. Do these results support the claim that the SAT prep course improves the students' verbal SAT scores?
Let d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course)d=(verbal SAT scores prior to taking the prep course)−(verbal SAT scores after taking the prep course). Use a significance level of α=0.1 for the test. Assume that the verbal SAT scores are normally distributed for the population of students both before and after taking the SAT prep course.
Student 1 2 3 4 5 6 7
Score on first SAT 500 380 560 430 450 360 560
Score on second SAT 540 470 580 450 480 400 600
Required:
a. State the null and alternative hypotheses for the test.
b. Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.
c. Compute the value of the test statistic. Round your answer to three decimal places.
d. Determine the decision rule for rejecting the null hypothesis. Round the numerical portion of your answer to three decimal places.
e. Make the decision for the hypothesis test.
Answer:
Since the calculated value of t = -0.215 falls in the critical region so we accept Ha that SAT prep course improves the students' verbal SAT scores and reject the null hypothesis at significance level 0.05.
e. These results support the claim that the SAT prep course improves the students' verbal SAT scores.
Step-by-step explanation:
Student 1 2 3 4 5 6 7
Score on first SAT 500 380 560 430 450 360 560
Score on second SAT 540 470 580 450 480 400 600
Difference d -40 -90 -20 -20 -30 -40 -40 ∑ -280
d² 1600 8100 400 400 900 1600 1600 ∑14600
a. Let the hypotheses be
H0: ud= 0 against the claim Ha: ud ≠0
The degrees of freedom = n-1= 7-1= 6
The significance level is 0.05
The test statistic is
t= d`/sd/√n
The critical region is ║t║≤ t (0.025,6) = ±2.447
d`= ∑di/n= -280/7= -4
Sd²= ∑(di-d`)²/n-1 = 1/n-1 [∑di²- (∑di)²n]
= 1/6[14600-(-4)²/7] = [14600-2.2857/6]= 2432.952
b. Sd= 49.3249= 49.325
Therefore
c. t= d`/ sd/√n
t= -4/ 49.325/√7
t= -4/18.6435 = -0.2145= -0.215
d. Since the calculated value of t = -0.215 falls in the critical region so we accept Ha that SAT prep course improves the students' verbal SAT scores and reject the null hypothesis at significance level 0.05
e. These results support the claim that the SAT prep course improves the students' verbal SAT scores.
joe used 20 gallons of gas to go 300 miles. At this rate, how much gas must he use to go 3500 miles?
STEP BY STEP ASAP PLEASE ITS EQIVALENT RATIO
Answer:
400 miles se tiene que multiplicar y sumar
Annabelle drove 155 miles in 5 hours. How many miles does she drive in 4 hours? How many miles does she drive in 6 hours?
josè and nancy take care of animals when the owners are away. josè charges $15 plus $2 per animal. nancy charges $5 plus $3 per animal. for how many animals do they charge the same amount?
get it right i will give you 100 points
Hey there! I'm happy to help!
Here's José's equation.
J=2a+15
And here is Nancy's.
N=3a+5
We want to find the number of animals where they are the same amount, or where J=N. We can write these equations as equal and solve for a to find the answer!
2a+15=3a+5
Subtract 15 from both sides.
2a=3a-10
Subtract 3a from both sides.
-a=-10
Divide both sides by -1.
a=10
Therefore, José and Nancy charge the same amount for 10 animals.
Have a wonderful day! :D
Which statement about histograms is true?
Data is organized in categories.
Data appears as bars that are all about the same height.
Data is organized in equal intervals.
Data appears as bars that do not touch.
Answer:
C
Step-by-step explanation:
CCCCCCCCCCCCCCCCCCCCCCCCC
Answer:Data is organized in equal intervals.
Step-by-step explanation:
What is the solution to the system of equations? =6x=y=8 5x+3y = 29 (10,-2) (10, 2) O (2, 10) (-2, 10)
Question 16 please help me
5x - 3 (x+3) = what to have infinitely many solutions
Answer: 1/4
Step-by-step explanation: I think that’s the answer! i’m sorry i’m in 8th fe are
Hello :)
Please help me solve this
Explain answer
Answer:
A. Store A will cost about $1.28 less
Step-by-step explanation:
Store A:
Unit rate = y/x
Using any given pair, say (3, 7.26),
Unit rate = 7.26/3 = $2.42 per gallon
So, of a customer is buying 16 gallons at Store A, he'd pay:
$2.42 * 16 = $38.72
Store B:
Unit rate = y/x
Using any point on the graph, say (20, 50),
Unit rate = 50/20 = $2.5 per gallon
So, of a customer is buying 16 gallons at Store B, he'd pay:
$2.5 * 16 = $40.
Cost of Store B - Cost of Store A = $40 - $38.72 = 1.28
This means that Store A cost about $1.28 less
What is the common factor of 26 and 38
Answer: The GCF is 2 and the LCF is 1
Step-by-step explanation:
Pls help as fast as u can
Answer:
Step-by-step explanation:
a)4.67
b) 2.27
do you not have a calculator? :/
Answer:
a. $2.2
b. $2.2
Step-by-step explanation:
Not completely sure if it's right for part b, but 100% sure my answer for part a is right.
In one class, there are 2 of every 8 students in the class chewing
gum. If there are 32 students in the class, how many students are
chewing gum?
Answer:
8
Step-by-step explanation:
Answer:
8 people are chewing gum
Step-by-step explanation:
32/8=4, meaning there are 4 sets of 8 students.
If 2 students are chewing gum for every 8, and there are 32 students, that would mean that multiplying 4 by 2 to get 8 total kids chewing gum.
You could also say that 6*4=24, and 32-24=8 if you want to double check.
Hope this helps :)
A standard train ticket in a certain city costs $1.50 per ride. People who use the train also have the option of purchasing a frequent rider pass for $17.25 per month. With the pass, a ticket costs only $0.75 per ride. How many train rides a month make the frequent rider pass a better deal than standard train tickets?
Just off the bat 17$is 12 rides and then 17.25 +0.75 is 18 so 13 rides
Is anyone here good at calculus I’m willing to pay.
Algebraic Expression
43 times greater than
the sum of 57 and 93
Find the values of the variables in the parallelogram.
Step-by-step explanation:
We can find x very easily because the left and right sides are parallel,making the diagonal connecting them a transversal therefore x=33°
To find y we know that the sum of interior angles of a triangle is 180°
y+109°+33°=180°
y+142°=180°
y=38°
Now,
x+38°+z=180
33+38+z=180
z=180-71=109°
Write an equation, and then solve.
5. Kiesha and Wanda went to the mall for 4.5 hours. While they were there, they went to a movie that lasted 130
minutes and ate dinner for 70 minutes. They spent the rest of the time walking around the mall. How long did
they spend walking around the mall?
Answer:
70 mins
Step-by-step explanation:
Lets first convert the 4.5 hours to minutes. We know that there's 60 mins in an hour, so we can just multiply 4.5 by 60 to get 270 minutes. Now we know the total time spent at the mall.
Then, we can add the times given in the question.
130 mins + 70 mins + walking mins = 270 mins
To solve, simply collect like terms:
200 mins + walking mins = 270 mins
walking mins = 270 mins - 200 mins
walking mins = 70 mins
Look at this please i dont need help im just trying to tell everybody something
Answer:
ok
Step-by-step explanation:
1-i need to mix 25% mineral spirits to the varnish i am using what ratio of spirit to varnish am i using? 2-if i use 240 ml of varnish what quantity of mineral spirits will i need in ml ? 3-Robison's tapestries all measure 1.5m x 1m wide. Express the proportion of the tapestries' heights to width using whole numbers. Give the answer in ration.
Answer:
(1) The required ratio of spirit to varnish is 1:3.
(2) You need 80 ml of mineral spirit.
(3) The ratio of tapestries' heights to width is 3:2.
Step-by-step explanation:
(1) If you need to mix 25% mineral spirit to the varnish, then the solution would contain 25% mineral spirit and 75% varnish.
So, [tex]\frac{spirit}{varnish}=\frac{25}{75}[/tex]
[tex]=\frac{1}{3}[/tex]
Thus, The required ratio of spirit to varnish is 1:3.
(2) If you use 240ml of varnish, then this quantity is 75% of the total solution or ration of varnish to the total solution will be 3:4.
Let [tex]x[/tex] be the quantity of total solution.
Then, [tex]240:x=3:4[/tex].
⇒[tex]\frac{240}{x}=\frac{3}{4}[/tex]
⇒[tex]3x=240*4[/tex]
⇒[tex]x=\frac{240*4}{3}[/tex]
⇒[tex]x=320[/tex]
That is, total solution is 320 ml.
Now, Spirit = Total solution - Varnish
⇒Spirit = 320ml-240ml
⇒Spirit = 80ml
Hence, if you use 240 ml of varnish, you need 80 ml of mineral spirit.
(3) Robison's tapestries all measure 1.5m long and 1m wide. First, we express dimensions in whole numbers by multiplying them by 10.
Then, dimensions are 15m long and 10m wide.
Now, Height : Width = 15:10
⇒[tex]\frac{Height}{Width} =\frac{15}{10}[/tex]
⇒[tex]\frac{Height}{Width} =\frac{3}{2}[/tex]
Hence, the ratio of tapestries' heights to width is 3:2.
Determine whether the system of linear equations has one and only one solution, infinitely many solutions, or no solution.
Answer:
only one solution
Step-by-step explanation:
Complete question:
Determine whether the system of linear equations has one and only one solution, infinitely many solutions, or no solution. 2x − y = 2 3x + y = −6 one and only one solution infinitely many solutions no solution Find the solution, if one exists. (If there are infinitely many solutions, express x and y in terms of the parameter t. If there is no solution, enter NO SOLUTION.) (x, y) =
Given the expression
2x − y = 2 .... 1
3x + y = −6 ..... 2
We are to determine the number of solution the equation has:
Add equation 1 and 2
2x + 3x = 2 - 6
5x = -4
x = -4/5
Substitute x = -4/5 into 1
From 1: 2x − y = 2 .... 1
2(-4/5) - y = 2
-8/5 - y = -2
-y = -2+8/5
-y = -10+8/5
-y = -2/5
y = 2/5
Since the value of x and y are just 1 hence the system of equations has ine solution
I will give you a good amount of points if you answer this correct
Answer:
I think the answer is B. The equation has infinitely many solutions.
Step-by-step explanation:
4(3x + 4) = 15x + 12 - 3x + 4
*group like terms so 4(3x+4) = 15x - 3x + 12 + 4
*add similar elements 15x - 3x = 12x
*add the numbers 12 + 4 = 16
*Expand to 12x + 16 - 16 = 12x + 16 - 16
*You simplify 12x = 12x
*Subtract 12x from both sides
*Then Simplify which is 0
Which means Both sides are equal to 0
True for all X
Please help ASAP!! 20 points givin
Answer:
d or b
Step-by-step explanation:
quick math
Write an expression that represents the number of shells in pile 2.
Answer:
2
Step-by-step explanation:
4/2=2
Tina contributes 9.5% of her monthly salary towards her 401(k) and her employer matches her contribution up to 5.4% of her annual salary. If the interest rate of her 401(k) is 8.1% compounded monthly and her monthly salary is $2,461, determine the amount in her account after 25 years. Round to the nearest cent.
a.
$339,804.33
b.
$354,452.86
c.
$344,941.24
d.
$347,269.59
Please select the best answer from the choices provided
A
B
C
D
Answer:
In 25 years, Tina will have $354,452.86
Step-by-step explanation:
Monthly Contribution - $366.69 (Tina & Employer)
Length of Time in Years - 25
Estimated Interest Rate - 8.1%
Compound Frequency - Monthly
please help y'all no matter what I do I cannot figure this out please help what number would you add to both sides to complete the square in this trinomial x ^ 2 + 6x = -5 and the options are 6 , 9 , 12 and please show how you did it so I can figure out the rest of my homework
Answer:
Im sorry im not sure
Step-by-step explanation:
Could somebody pls help me with this question
Answer:
18 minutes is the answer
Step-by-step explanation:
•Time couple rested in 2 hrs = 12 min
•Time couple rested in 1 hr = 12/ 2 min = 6min
•Time couple rested in 3 hrs = 6×3 min = 18 min
HOPE IT HELPS YOU
MARK ME AS BRAINIEST
AND YOU CSN THANK ME IN THE COMMENT
Tyree and four friends go to the movies. Each person buys a movie ticket for $7, a snack for $5, and a drink for $2. Write an expression for the total cost of the trip to the movies. Then find the total cost.
Answer:
Tyree and all of his friends get 1 ticket for $7. Next they all get 1 snack for $5. Then they all get a drink for $2. So:
1=7
1=5
1=2
Then you take each person (which there are five of then) and you times all five people by 7, 5, 2.
5 x 7=35
5 x 5=25
5 x 2=10
After that you add it all together:
35 plus 25=60
60 plus 10=70
Step-by-step explanation:
your welcome
Answer:
Im not sure if it ment, Tyree and four friends go to the movies. Each person buys a movie ticket for $7, a snack for $5 (meaning only one snack), and a drink for $2. (Meaning only one drink) or if it ment Tyree and four friends go to the movies. Each person buys a movie ticket for $7, a snack for $5 (meaning everyone got a snack), and a drink for $2(meaning everyone got a drink). So i did the math for both of them, if they only got 5 tickets, one snack, and one drink, it would be 42 (the math problem is 35 + 2 + 5). if they got 5 tickets, 5 snacks, and 5 drinks, it would be 70(the math problem is 35 + 25 + 10). Hope this helps!
800 adults were surveyed to find out how many notes per week they cook dinner 60% indicated that they cooked dinner more than four nights at per week based on the results of the survey how many adults out of a group of 2000 to cooked dinner more than four nights per week
Answer:
1200
Step-by-step explanation:
60 x
- = -
100 800
There are 2 ways to solve this.
1) 800 x 60= 48,000
Divide by 100= 480
x=480
2) Multiply 60 by 8.
Now there are another 2 ways to go.
1) 480 x
- = -
800 2000
OR2) 60 x
- = -
100 2000
I recommend the second option for both. It is easier. The second option allows you to find and equal ratio, with less of the hassle.To get 2000, 100 must be multiplied by 20. So.... multiply 60 by 20 to get a equal ratio.
Your answer is 1200. Meaning 1200 adults cooked dinner more than four nights per week.
I hope this helps you significantly
~~~LampteyJ
Answer:
1200
Step-by-step explanation:
(-7-3i)(11-8i)
Simplified into the a+bi form
Answer: what
Step-by-step explanation:
7 1/2 + X + 15? What is X?
