An education researcher would like to test whether 2nd graders retain or lose knowledge during the summer when they are presumably not in school. She asks nine 2nd graders to take a comprehension exam at the end of the school year (May), and then asks those same students to come back after the summer (late August) to retake a different but equivalent exam, to see if their level of comprehension has changed. Using the data below, test this hypothesis using an alpha level of .05.
May August
90 100
65 80
78 92
50 60
89 90
92 98
75 70
90 96
65 87
a) What is the appropriate test? Is it a one or two tailed test?
b) State the null hypothesis (in words and using means).
c) State the alternative hypothesis (in words and using means).
d) Find the critical value.
e) Calculate the obtained value by hand. What does your decision mean?
Answer:
See step by step explanation
Step-by-step explanation:
From the problem statement, we understand that we need to investigate if 2nd graders RETAIN OR LOSE knowledge comparing information concerning two different months, therefore we are going to find out if the information gives us enough evidence of a difference in the two groups
a) The test should be a two tail-test
Sample sizes are small ( n₁ = n₂ = 9 ) which means we have to use t-student test
b and c) Test Hypothesis:
For Null Hypothesis H₀, we establish that the two means are equal, which in this case means that the two samples´ means are equal. And as Hypothesis alternative Hₐ that the H₀ is not true, or that the samples mean are different.
Null Hypothesis H₀ x₁ - x₂ = 0 or x₁ = x₂
Alternative Hypothesis Hₐ x₁ - x₂ ≠ 0 or x₁ ≠ x₂
d) Significance level α = 0,05 then α/2 = 0,025
then t(c) with α/2 = 0,025 and degree of freedom
df = n₁ + n₂ - 2 df = 9 + 9 -2 df = 16
From t s-tudent table we find t(c) = 2,12
e) Calculating:
x₁ and σ₁
x₂ and σ₂
σₓ = [ ( n₁ - 1 )* σ₁² + ( n₂ - 1 )*σ₂² ]/ n₁ + n₂ - 2
Using a calculator:
x₁ = 77,11 σ₁ = 13,86
x₂ = 85,89 σ₂ = 12,74
σₓ = [ ( 8*(13,86)² + 8*( 12,74 )² ] / 16
σₓ = (8* 192,1) + 8* ( 162,31) / 16
σₓ = (1536,8 + 1298,48 ) / 16
σₓ = 177,205
t(s) = ( x₁ - x₂ ) /√ σₓ²/ n₁ + σₓ²/ n₂
t(s) = ( 77,11 - 85,89 )/ (177,205)²/n₁ + (177,205)²/n₂
t(s) = - 8,78 / √3489,07 + 3489,07
t(s) = -8,78 / 83,54
t(s) = - 0,11
Comparing t(s) and t(c)
|t(s)| < |t(c)|
0,11 < 2,12
t(s) is in the acceptance region. We accept H₀
If x= 10 which lines are parallel? Check all that apply. (8x - 25) b (12x - 5) (7x - 5) (10x + 15) a
Answer:
150 A
Step-by-step explanation:
THIS THE ANSWER
I HOPE IT HELPS
help me asap please help me help thank you
Answer:
H
Step-by-step explanation:
Area of a square is given as 16 unit²
Since formula of square is
A=l²
16=l²
l=√16
=4
pls help asap, ill give brainiest
The answer is D
If this helped a brainliest would be appreciated!
which is the smallest integers, please answer, -9, 0, -2, -4, -11
Answer:
-11 :)
Step-by-step explanation:
Answer: 0
Step-by-step explanation:
A pet store has
10 hamsters for every 8 cats.
What is the ratio of hamsters to cats?
8:18
8:10
10:8
Answer: 10:8
Step-by-step explanation:
There are 10 hamsters and 8 cats
Since hamsters is first in the ratio, you put the 10 and then the 8
10:8
Hope this helps!
Answer:
the last option 10:8....
Chris has 150 Pokemon cards. Each week,
Chris purchases 15 Pokemon cards to add
to his collection. Which inequality can be
used to find w, the number of weeks after
starting his collection when Chris will have
more than 500 Pokemon cards in his
collection?
A.
150w + 15 < 500
B.
15W + 150 < 500
C.
150w + 15 > 500
Need He
D.
15W + 150 > 500
Answer:
D
Step-by-step explanation:
He already has 150 cards and he is buying 15 cards EACH WEEK. W represents the amount of weeks and since 15W +150 needs to be greater than 500 we need to use this lil guy (>)
Rewrite by completing the square f(x) = x2 - 6x +43
Answer:
f(x) = (x - 3)^2 + 34
Step-by-step explanation:
Find the 8th term of the geometric sequence show below
Answer:
Alli khanaw .................
Answer:
8x^36
Step-by-step explanation:
first term (a) = [tex]8x^{8}[/tex]
Second term (t2)= [tex]8x^{12}[/tex]
common ratio (r)
= [tex]\frac{8x^{12} }{8x^{8} }[/tex]
= [tex]x^{4}[/tex]
now the 8th term of the G.S is
t8 = [tex]ar^{n-1}[/tex]
= [tex]8x^8 * (x^4)^8^-^1[/tex]
= [tex]8x^8 * (x^4)^7\\[/tex]
= [tex]8x^8 *x^2^8\\= 8x^3^6[/tex]
hope it will help
'All factors of 70 are even numbers.'
Is he correct?
Ores
Yes
No
No
Explain your answer.
Answer:
No
Step-by-step explanation:
70 is divisible by 5. 5 is not an even number.
Answer:
No
Step-by-step explanation:
The factors of 70 are 1, 2, 5,7,10, 14, 35, and 70. the even numbers are 2, 10,14, and 70. but there are odd numbers, like 1, 5, 7, and 35. And since we know there are odd factors, the answer is No. 70 has even AND odd factors.
HELP ME I NEED THIS SO BADLY AND QUICK IF POSSIBLE
Answer:
B
Step-by-step explanation:
Help. What’s the answer to this problem?
Answer:
C) Yes, it’s a reflection over line f.
Step-by-step explanation:
It’s a reflection over line f.
Question 1 of 10
Which function results after applying the sequence of transformations to
Rx) = x5?
• compress vertically by
• shift left 2 units
• shift down 1 unit
O A. g(x) = }(x-2)5.1
O B. g(x) = + (x + 2,5-1
O C. g(x) = (3x+2)5-1
O D. g(x) = ž (x-1)5-2
HELP PLEASE ❗️❗️❗️❗️
Answer:
A (g(x) = }(x-2)5.1).
Step-by-step explanation:
The function which results after the sequence of transformations given is B. g(x) = 1/2 (x + 2)⁵ - 1.
What is Translation of Functions?Translation of functions is defined as the when each point in the original graph is moved by a fixed units in the same direction.
There are horizontal translation and vertical translation of functions.
Given function is,
f(x) = x⁵
When a function is compressed vertically, then new function formed will be of the form, k f(x), where k is the factor that is compressed.
After compress vertically by 1/2,
f(x) changes to 1/2 f(x) = 1/2 x⁵
After the horizontal translation of 2 units to the left,
1/2 f(x) changes to 1/2 f(x + 2) = 1/2 (x + 2)⁵.
After vertical translation of 1 unit to the down,
1/2 f(x + 2) changes to 1/2 f(x + 2) - 1 = 1/2 (x + 2)⁵ - 1
Hence the correct option is B . g(x) = 1/2 (x + 2)⁵ - 1.
Learn more about Transformations of Functions here :
https://brainly.com/question/13810353
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Show your full solution
1. How much larger is the pizza in a circular pan with a 14-inch diameter than a pizza made in square pan with sides measuring 14 inches?
2. A photograph measuring 10 cm by 4 cm is mounted on a rectangular cardboard, to leaving a margin of 3 cm all around. What is the area of a photograph?
Answer:
1.the square pan is larger by 12 inches
40 cm^2
Step-by-step explanation:
The difference in size can be determined by calculating the difference between the perimeter of the square pan and the circumference of a circle
perimeter of a square = 4 x length
14 x 4 = 56 inches
Circumference of a circle = πD = (22/7) x 14 = 44 inches
Difference in size = 56 - 44 = 12 inches
Area of a rectangle = length x width
10 x 4 - 40 cm^2
-. For the event of rolling three standard fair 6-sided dice, find the following probabilities. Give all
answers as a simplified fraction.
The probability of rolling a sum of 8 or a sum of 12.
P(Sum is 8 u Sum is 12)
Answer:
23/108
Step-by-step explanation:
Remark
There are 6 * 6 * 6 = 216 ways that you can throw three dice. There are 21 different ways of throwing an 8There are 25 different ways of throwing a 12I'll list the eights. The 12s are done the same way.Ways of making Eight
116125134143152161215224233242251314323332341413422431512521611Answer
P(8) = 21 / 216
P(12) = 25/ 216
P(8 or 12) = 21/216 + 25/216
P(8 or 12) = 46/216 = 23/108
For every 2 hours, approximately $1,186 worth of product is sold to consumers. How much money will the company for an entire month (30 days)?
I believe that the answer is $426,960.
I hope this helps!
Subtract -21 from 30
Answer:
-9
Step-by-step explanation:
yu subtract 21 from 30 and and just add a negative before the answer
Write the equation of a sine function that has the following characteristics.
Amplitude: 7 Period: 9π Phase shift: 1/4
Type the appropriate values to complete the sine function.
Answer:
[tex]\boxed{ \displaystyle y = 7\sin\left(\frac{2}{9}x-\frac{1}{4}\right)}[/tex]
Step-by-step explanation:
we want to figure out the equation of a sine function that has the following characteristics.
Amplitude: 7Period: 9π Phase shift: 1/4the standard form of sine function is given by
[tex] \displaystyle y = a\sin(bx-c)+d[/tex]
where:
a is the amplitudeb can be sorted out using the equation 2π/b=periodC refers to phase shiftFinding a and phase shift:
a and c is simply given which is
a=7C=¼finding b:
using the equation we acquire:
[tex]\dfrac{2\pi}{b}=9\pi[/tex]
solving the equation for b,we obtain:
b=2/9
finding d:
Since d Isn't mentioned, we would assume it 0
finding the equation:
substitute what we got:
[tex]\boxed{ \displaystyle y = 7\sin\left(\frac{2}{9}x-\frac{1}{4}\right)}[/tex]
and we're done!
(4) A sign on the road says: "Speed limit, 60 mph." Let s be the speed of a car. Choose the correct inequality that matches the information on the sign. the answers are= s<60 , s=60 , s<60 , s>60
Step-by-step explanation:
Choose the correct inequality that matches the information on the sign. the answers are
s<60
Help thanks in advance
Answer:
C) 2/7, 1/2, 5/6, 4/2
Step-by-step explanation:
adadaadadadadadadadad
Answer:
I think B and D
Step-by-step explanation:
I’m not 100% sure tho
please help I'll give brainliest
You are wrapping a cube shape present that is 1.5 feet tall. How much wrapping paper will you need to wrap the entire present?
the answer is going to be 6.0
Step-by-step explanation:
1.5 + 1.5 = 3
3 + 3 = 6
32614 round to nearest 100 place?
Answer:
32600
Step-by-step explanation:
Use technology or a z-score table to answer the question.
The number of baby carrots in a bag is normally distributed with a mean of 94 carrots and a standard deviation of 8.2 carrots.
Approximately what percent of the bags of baby carrots have between 90 and 100 carrots?
23.3%
31.2%
45.5%
76.73%
Answer:
46% is the percent of the bags of baby carrots that have between 90 and 100 carrots
Step-by-step explanation:
The baby carrot is normally distributed.
z = (x - µ)/σ
x is equal to number of baby carrots
µ = mean
σ = standard deviation
Substituting the given values, we get -
90 ≤ x ≤ 100
z = (90 - 94)/8.2 = - 0.49
For z value of -0.49, the probability is 0.31
For x = 100
z = (100 - 94)/8.2 = 0.73
For z value of 0.73, the probability is 0.77
P(90 ≤ x ≤ 100) = 0.77 - 0.31 = 0.46
The percent of the bags of baby carrots having carrots between 90 and 100 carrots is 0.46 × 100 = 46%
I need help figuring this out, thank you! :)
Answer: 8
Step-by-step explanation:
5*6/2=15120/15=8A 6-sided die rolled twice. Let E be the event the first roll is a 5 and F the event "the second roll is a 5".
(a) Are the events E and F independent? |
Input Yes or No: Yes
(b) Find the probability of showing a 5 on both rolls. Write your answer as a reduced fraction.
Answer:
How many miles will light travel in one day if the speed of light is 300,000,000 meters per second.
(1.62 km = 1 mi)
Answer:
[tex]d=1.61\times 10^{10}\ miles[/tex]
Step-by-step explanation:
Given that,
The speed of light, v = 300,000,000
eWe need to find the distance light travel in 1 day. We know that,
1 day = 86400 seconds
Distance = speed × time
So,
[tex]d=3\times 10^8\times 86400[/tex]
[tex]d=2.592\times 10^{13}\ m[/tex]
or
[tex]d=0.001610\times 10^{13}\\\\d=1.61\times 10^{-3}\times 10^{13}\\\\d=1.61\times 10^{10}\ miles[/tex]
So, the required distance is equal to [tex]1.61\times 10^{10}\ miles[/tex].
Find the erea of the trapezoid.
9514 1404 393
Answer:
32 yd²
Step-by-step explanation:
Use the area formula with the given dimensions.
A = 1/2(b1 +b2)h . . . . . base lengths b1, b2; height h
A = 1/2(2 +6)8 = 1/2(8)(8) = 32 . . . . square yards
The area of the trapezoid is 32 square yards.
evaluate (11.6)^2 by using (a^2+b^2+2ab)
Answer:
[tex]134.56[/tex]
Step-by-step explanation:
Break 11.6 into addenda.
[tex](11 + 0.6)[/tex]
Apply the binomial expansion method.
[tex](11 + 0.6)(11 + 0.6)[/tex]
[tex]11 {}^{2} = 121[/tex]
[tex]2(11)(0.6) = 13.2[/tex]
[tex]0.6 {}^{2} = 0.36[/tex]
Add them all up and you get.
[tex]134.56[/tex]
I need help please. I need the the discount and selling price. Thank you
Answer:
15.12 is the discount68.88 is the sell priceStep-by-step explanation:
When you are taking off percentages from numbers, you first want to make the percent a number. This step is super simple. Just divide the 18 by 100
This gets you 0.18
Now multiply
84 * 0.18 = 15.12
So 15.12 is the discount
Then take 84 and subtract 15.12
84 - 15.12 = 68.88
So 68.88 is the sell price
