Answer: 10 quarters, 5 dimes.
Explanation:
10 x .25 = 2.50
5 x .10 = .50
2.50 + .50 = 3.00
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%).
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
Add 12 and 8 and then divide by 8 as an expression help please
Answer:
(12 + 8)/8 = 2.5
Answer:
12 + 8/8 =?
20/8 =?
20/8 = 2.5
Step-by-step explanation:
•°•°•°•°•°•°•
GUYS PLEASE ASAP I WILL FAIL IF U GUYS DONT ANSWER PLEASE
WHICH ONE IS INCORRECT
Answer:
The table
Step-by-step explanation:
The puppy weighs 0.8 pounds at birth not 0
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
Write the expanded form 38.65 in a decimal form
Answer:38.65 = 30 + 8 +6/10+5/100
Step-by-step explanation:
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
Which definition best describes a linear pair?
A. A pair of angles that combine to form a straight angle
B. A pair of angles whose sum is 360°
O C. A pair of opposite angles formed by intersecting lines
D. A pair of angles whose sum is 90°
SUBMIT
Answer:
A or C
Step-by-step explanation:
well, two angles are a linear pair if the angles are adjacent and the two unshared rays form a line. The linear pair postulate states that two angles that form a linear pair are supplementary
Hope this helps
Linear pair example below:
help lol the last answer choice is y=5/3x-10
Answer:
C
Step-by-step explanation:
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:
Let g(x)=4x +9 and h(x)=x+2. Find the expression.
(h◦g)(x)
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
Complete the equation of the line through (4,-8) and (8,5)
Use exact numbers.
Y=?
The Answer:
y=3.25x+ (-21)
Answer:
y-intercept = (0, -21)
Step-by-step explanation:
Find the value of the slope.
[tex]m = \frac{13}{4} [/tex]
Find the value of the y-intercept.
[tex]b = - 21[/tex]
List the slope and y-intercept.
Slope: 13/4
y-intercept: (0, -21)
Elimination
3x +2y=9
3x ty=0
1
Answer:
[tex]y = 9[/tex]
[tex]x = -3[/tex]
Step-by-step explanation:
Given
[tex]3x + 2y = 9[/tex]
[tex]3x + y = 0[/tex]
Required
Solve by elimination
To do this, we subtract both equations (to eliminate x)
[tex]3x + 2y = 9[/tex]
- [tex]3x + y = 0[/tex]
--------------------
[tex]3x - 3x + 2y - y = 9-0[/tex]
[tex]y = 9[/tex]
Substitute [tex]y = 9[/tex] in [tex]3x + y = 0[/tex]
[tex]3x + 9 = 0[/tex]
Solve for 3x
[tex]3x =- 9[/tex]
Solve for x
[tex]x = -9/3[/tex]
[tex]x = -3[/tex]
whats
455
x 6
-----------
Answer:
2730
Step-by-step explanation:
Answer:
2730................:)))))))))))))
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
Find the area of the figure.
Answer:25
Step-by-step explanation:
cur figure up into two small triangles, one recrtangle and a big triangle
30 mm
40 mm
What is the length of the hypotenuse?
Answer:
50 mm
Step-by-step explanation:
I remembered the 345 triangle, so it applies here.
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
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
What is the volume of a cube with a side length of 2/5 cm?
What is the volume of a cube with a side length of 2/5 cm? 0.4 cm
Answer:
8/125 cm³
Step-by-step explanation:
(2/5)³=2³/5³
= 8/125 cm³ or 0.064
Name the song that goes with these lyrics
1. I was rocking off white tryna have a fun time she gone eat like lunch time molly got her on time
2. Im a first class baby u in last baby im a 90's baby but i cook that shi from the 80's
3. I know i have a purpose but ion see the purpose they tell me the death of me gone be the perkys i know the lace the pills i bought them on purpose lifes unreal when deaths uncertain
Answer: first one is “I’ll be fine”
second one is “On God”
third one is “Rich and Blind”
At Walmart™ you can buy 8 hot dog buns for $2. At Costco™ you can buy the same hot dog buns, but they are $5.60 for 16 hot dog buns. Using two tables, decide who has the better deal (who sells 1 hot dog bun for the cheaper price).
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
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?
V + 3 = -V + 25
a. -9
b. 9
c. 11
d. -11
Answer:
c.11 is coorrect
Step-by-step explanation:
V+3=-V+25
shift same type of variables on one side
V+V=25-3
2V=22
V=22/2
V=11
Need help take your time and thx
Answer:
(x-4) (x+1)
step by step explanation:,
solve: 1/3a²-1/a=1/6a²
Pls answerwer for me
helpppp plzzzzzzzzzzzzz
I know it’s supplementary but I can’t find the value of X
Answer:
x = 18
Step-by-step explanation:
Answer:
x = 18
Step-by-step explanation:
Supplementary angles = 180°
110° + ( 3x + 16° ) = 180
110° + 3x + 16 ° = 180
126° + 3x = 180
3x = 180 - 126
3x = 54°
x = 54/3
x = 18
