Answer C
steps
deduct 10 from 26
26-10 which will give us 16
Researchers investigated whether providing a fancy, foil-wrapped piece of chocolate with the dinner bill would lead to higher tips than not providing such a treat. Sixty-four dinner parties at a restaurant in Ithaca, NY were randomly assigned to receive such a piece of chocolate or not with their dinner bill. Of the 32 parties who received the chocolate, the average tip (as a percentage of the bill) was 17.84%, with a standard deviation of 3.06%. Of the 32 parties who did not receive the chocolate, the average tip (as a percentage of the bill) was 15.06%, with a standard deviation of 1.89%. Determine a 96% confidence interval for the size of the difference in average tips between the two groups
Answer:
The 96% confidence interval for the size of the difference in average tips between the two groups is (1.47%, 4.09%).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.
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.
Subtraction of normal variables:
When we subtract normal variables, the mean is the subtraction of the means while the standard deciation is the square root of the sum of the variances.
Of the 32 parties who received the chocolate, the average tip (as a percentage of the bill) was 17.84%, with a standard deviation of 3.06%.
This means that:
[tex]\mu_{C} = 17.84, s_{C} = \frac{3.06}{\sqrt{32}} = 0.541[/tex]
Of the 32 parties who did not receive the chocolate, the average tip (as a percentage of the bill) was 15.06%, with a standard deviation of 1.89%.
This means that:
[tex]\mu_{NC} = 15.06, s_{NC} = \frac{1.89}{\sqrt{32}} = 0.3341[/tex]
Difference in average tips
The distribution has mean:
[tex]\mu = \mu_{C} - \mu_{NC} = 17.84 - 15.06 = 2.78[/tex]
Standard deviation:
[tex]s = \sqrt{s_{C}^2 + s_{NC}^2} = \sqrt{0.541^2 + 0.3341^2} = 0.6358[/tex]
96% confidence interval
We have that 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 - 0.96}{2} = 0.02[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.02 = 0.98[/tex], so Z = 2.054.
Now, find the margin of error M as such
[tex]M = zs[/tex]
[tex]M = 2.054*0.6358 = 1.31[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 2.78% - 1.31% = 1.47%
The upper end of the interval is the sample mean added to M. So it is 2.78% + 1.31% = 4.09%
The 96% confidence interval for the size of the difference in average tips between the two groups is (1.47%, 4.09%).
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Answer:
wait what?
Step-by-step explanation:
Find the perimeter of quadrilateral ABCD. Round your answer to the nearest hundredth. A(3, 5) B(1, 3) C(3, -1) D(5, 3)
Answer:
Perimeter = 4(√2 + √5) units
Step-by-step explanation:
Given:
Quadrant of 4 points;
A(3, 5) B(1, 3) C(3, -1) D(5, 3)
Find:
Perimeter
Computation:
Distance = √(x1 - x2)² + (y1 - y2)²
Distance between AB = √(3 - 1)² + (5 - 3)²
Distance between AB = √4 + 4
Distance between AB = 2√2 units
Distance between BC = √(1 - 3)² + (3 + 1)²
Distance between BC = √4 + 16
Distance between BC = 2√5 units
Distance between CD = √(3 - 5)² + (-1 - 3)²
Distance between CD = √4 + 16
Distance between CD = 2√5 units
Distance between DA = √(5 - 3)² + (3 - 5)²
Distance between DA = √4 + 4
Distance between DA = 2√2 units
Perimeter = sum of all sides
Perimeter = 2√2 + 2√5 + 2√2 + 2√5
Perimeter = 4√2 + 4√5
Perimeter = 4(√2 + √5) units
7. You roll a standard dice twice and flip a coin. What is the probability you 5 points
roll a 5, roll a 3 and then flip heads? *
Answer:
can you just mark me brainlest
Step-by-step explanation:
Answer:
the answer would probably
Step-by-step explanation:
PAY ATTENTION IN CLASS AND YOU WOULD KNOWWW
x - 75 = 200
whats the answer make sure to do a explanation
Answer:
275
Step-by-step explanation:
x- 75 = 200
add 75 to both sides of equation
x = 275
whats
455
x 6
-----------
Answer:
2730
Step-by-step explanation:
Answer:
2730................:)))))))))))))
Your employer offers a retirement plan which pays 8.5% compounded monthly. If
you deposit $420 / month for 47 years into this retirement plan, how much money
will you have in this account 47 years from now?
Answer:$19,740
Step-by-step explanation:
Hope its right.
Factor the expression (x+4)^2-4y^5(x+4)+4y^10
What is the equation of the line that passes through the point (-3, 7) and has a
slope of —3
Answer:
y=-3x-2
Step-by-step explanation:
Equation of a line is y=mx+b, where m is the slope given, -3.
Y=-3x+b
To find b, sub in the points (-3,7) for x and y in the equation
7=-3(-3)+b
7=9+b
-2=b
URGENT PLEASE HELP !!!
Answer:
36
Step-by-step explanation:
AB=AC+BE
AB=10+26
AB=36
PLEASE HELPP ASAPPP will mark brainlist
Answer:
I think this is the answer for the second question.
PLEASE HELP I WILL GIVE BRAINLY I PROMISE AND NO LINKS PLEASE :)))))))))))A gardener made a scale drawing of a lawn with a scale
factor of 1:8. The dimensions of his drawing are 9 inches
long by 5 inches wide. His partner plans to make another
scale drawing of the lawn, but with a scale factor of
1:16.
What are the dimensions of this scale drawing?
Answer:
c the length is 4.5 inches width is 2.5
Step-by-step explanation:
Answer:
The anwser would be C !! The length is 4.5 inches width is 2.5 !
Step-by-step explanation:
Hope this helped!! :D
It takes 36 nails to make 4 chairs.
How many nails are needed to make 9 chairs?
A. 72
B. 81
O c. 144
O D. 162
O E. 324
Answer:
36/4=9 so each chair takes 9 nails so 9*9=81
B:81
What is the theme of the poem "Queen of the Cats"?
Answer:
Isu has a cat named Bashet. This one of the many names of the goddess Bast, queen of cats. He has siamese-type traos; his body has a ply tan ned hair, while his legs, tail, face and ears are so dark brown. Brown gradually blends into the most plida color. The cat just a normal cat, but Isu treats it with special reverence
Step-by-step explanation:
What is the value of 4 + 5x when x = 3?
A: 11
B:12
C:17
D:19
Answer:
the answer is D) 19
Step-by-step explanation:
5×3=15
4+15=19
Pls Help Me find the Area T-T
Answer:
the answer is 55m^2 I think
Answer:
55 is the Area
Step-by-step explanation:
4 x 10 = 40
5 x 3 = 15
15 ÷ 2 = 7.5
5 x 3 = 15
15 ÷ 2 = 7.5
7.5 + 7.5 = 15
40 + 15 = 55
Give Me Brainllest
find the difference quotient of the rational function, r(t) = -3/t+6
Answer:
r(t)= -3/t+6
r(t)= -3/6t=6
Answer: the answer is D
Step-by-step explanation:
Just did the assignment rn
25 Point Reward please help
Answer:
I think its 75
Step-by-step explanation:
I am honestly not very sure myself but I did really do this
Point Z is the incenter of triangle RST. Point Z is the incenter of triangle S R T. Lines are drawn from the points of the triangle to point Z. Lines are drawn from point Z to the sides of the triangle to form right angles and line segments Z A, Z B, and Z C. Angle A S Z is (5 x minus 9) degrees and angle Z S B is 16 degrees. What is the value of x? x = 2 x = 3
9514 1404 393
Answer:
x = 5
Step-by-step explanation:
SZ is the angle bisector of angle S, so ...
∠ASZ = ∠ZSB
5x -9 = 16
5x = 25 . . . . . . add 9
x = 5 . . . . . . . . .divide by 5
Answer:
C
Step-by-step explanation:
mhm
please answer and explain #17 :)
Answer:
Solution given:
we have
m<PTQ=m<RTS
x+20=3x+12.
20-12=3x-x
x=
[tex] \frac{8}{2} [/tex]
now
16.m<PTQ=x+20=4+20=24°
17.
again
m<PTR+m<PTQ=180°[supplementary]
so
m<PTR=180°-24°=156° is your answer
Answer:
156°
Step-by-step explanation:
I see you have already found the x so now plug it in.
(4)+20=24
(4)(3)+12= 24
Since they are vertical angles, then they are congruent, thats why they are equal. By now I think you should know that a straight line is equal to 180, so lets take 1 angle to find the missing one.
We can also see that ∠PTR and ∠RTS are also vertical angles, so they are also congruent. So we only use one, 180-24=156
the answer is 156 because ∠PTR and ∠PTQ are in the same line making them supplementary.
Does that make sense?
square root of 2800
Answer:
52.91 :)
Step-by-step explanation:
solve by regrouping 2x2+6x+54+18x
Answer:
I believe the answer is=2x2+342.
What is mfg angle 130 90 80
fg =
Answer:
arc FG = 60°
Step-by-step explanation:
arc FG = 360 - 130 - 90 - 80 = 60°
Answer:
FG would be 60 Degrees
Step-by-step explanation:
A circle is equivelent to 360 degrees
Permudahkan ungk
8a + 3b - 2a - b
Answer:
answer:8a + 3b - 2a - b
=8a-2a+3b-b
=6a+2b or 2(3a+b) is your answer
I
Which ordered pair could you add to the following list of points to
create a function? (3,5) (4, 9) (2,5)
(4, 1)
(2,6)
(3,7
(1,9)
Answer:
2-6
Step-by-step explanation:
5 673226
Pls answer i will give brainliest pls
Answer:
B
Step-by-step explanation:
In the slope intercept equation of the line the number that not multiplies the x or the y indicates where the line intercept the y axis
so in this cas the line intercept the y axis in the point (0,2)
so the answer is B
Let g(x)=4x +9 and h(x)=x+2. Find the expression.
(h◦g)(x)
If you flip three fair coins, what is the probability that you'll get heads on the first two flips and tails on the
last flip?
Answer:
1/8
Step-by-step explanation:
Khan Academy
Answer:
1/8
Step-by-step explanation:
Khan Academy
9. Susan wants to paint a room in her house. After measuring the walls, the total area is 532 square feet. A gallon of paint covers 150 square feet. Each gallon of paint costs $35. How much will it cost to paint the room? Show your work using unit fractions!
Answer:
will look into this answer
Joyce packed lunches for the Shiloh Football Team. If she packed 75 pounds of bagged lunches. Each bag weighed 1 1/2 pounds. How many lunches did she pack?
50
60
70
80
WILL GIVE BRANLIEST
Answer:
50
Step-by-step explanation:
total weight=75 pounds
each bag weighed 1 1/2 pound=3/2 pound
no. of lunches=total weight/weight of each lunch
=75/(3/2)
=75*2/3
=50lunches
Answer:
50
Step-by-step explanation:
You need to divide 75 lb by 1 1/2 lb.
[tex] 75 \div 1 \frac{1}{2} = 75 \div \dfrac{3}{2} = \dfrac{75}{1} \times \dfrac{2}{3} = \dfrac{150}{3} = 50 [/tex]
Answer: 50
