Two ride-sharing companies are competing for business in a large city. To help customers compare the companies, a data scientist selects a random sample of 40 completed rides from each of the two companies. From each sample, he computes the mean amount of time that passed between when the request for a pickup was placed and when the customer was picked up. Company A took, on average, 18 minutes to pick up customers with a standard deviation of 4 minutes. Company B took, on average, 12 minutes to pick up customers with a standard deviation of 10 minutes. (a) Construct and interpret a 98% confidence interval for the difference in mean response time for these two ride-sharing companies.
Solution :
Given :
[tex]$n_1 = n_2 = 40$[/tex]
[tex]$\overline X_1 = 18$[/tex]
[tex]$S_1 = 4$[/tex]
[tex]$\overline X_2 = 12$[/tex]
[tex]$S_2 =10$[/tex]
So we want to test :
[tex]$H_0 : \mu_1=\mu_2 $[/tex] vs [tex]$H_1 : \mu_1 \neq \mu_2 $[/tex]
a). For 98% confidence interval :
[tex]$=\left((\overline X_1 - \overline X_2) \pm Tn_1+n_2-2, \alpha / 2 \sqrt{\frac{s_1^2}{n_1}+\frac{s_2^2}{n_2}}\right)$[/tex]
[tex]$=\left((18-12) \pm 2.375 \sqrt{\frac{4^2}{40}+\frac{10^2}{40}}\right)$[/tex]
[tex]$=(6 \pm 4.0445)$[/tex]
= (1.956, 10.045)
HELP PLEASE ASAP!!!!! 20 POINTS!!!!
Online entertainment streaming services have gained in popularity in recent years as an alternative to traditional television. One such company has seen steady growth in each period of 3 months, called a quarter, over the past 4 years. The scatterplot shows the relationship between the number of quarters passed since January 2014 and the number of members to the streaming service. A least-squares equation that summarizes this relationship is members hat = 1.829 (quarters) minus 18.108, with a value for r of 0.991.
A graph titled subscribers versus quarters since January 2011 has quarters since January 2011 on the x-axis, and subscribers on the y-axis. Points are in a line with positive slope.
A graph titled Residuals versus quarters since January 2011 has quarters since January 2011 on the x-axis, and Residual on the y-axis. The points curve down, and then curve up.
Based on the residual plot, is a linear model appropriate for summarizing this relationship?
A linear model is appropriate because the value of r is close to 1.
A linear model is appropriate because the residual plot is curved.
A linear model is not appropriate because the residual plot shows a clear pattern.
A linear model is not appropriate because the scatterplot relating time and subscribers shows a clear pattern.
Answer:
c hope it nhelps
Step-by-step explanation:it takes away time
Answer:
the person above me is correct!
Step-by-step explanation:
Give two examples of line segments that will make a triangle ?
Answer:
If the length of any one side is greater than the sum of the length of the other two, the line segments cannot be used to create a triangle. It is possible to create a triangle using 3 line segments if the sum of the lengths of any two line segments is greater than the length of the third.
A picture of Margo's garden is shown below. It is made of 2 rectangular prisms. She wants to fill it with dirt. She needs to find the volume of the garden to know how much dirt to buy.
9 cubic feet
10 cubic feet
98 cubic feet
107 cubic feet
Answer:
9 cubic feet
Step-by-step explanation: You multiply them all then divide 9 by the greatest number that fits in 107The trajectory of a golf ball in a chip from the rough has a parabolic pattern. The height, in feet, of the ball is given by the equation h(x)=−.15x2+3.2x, where x is the number of feet away from the golf club (along the ground) the ball is.
The ball reaches a maximum height of _______ feet at a horizontal distance of ____
feet away from the golf club it was hit with.
The ball returns to the ground at about ________ feet away.
9514 1404 393
Answer:
maximum height of 17.07 feet about 10.67 feet from the club
returns to the ground 21.33 feet away
Step-by-step explanation:
A graphing calculator can answer these questions easily.
The vertex of the quadratic ax²+bx+c is given by x=-b/(2a). For this quadratic function, the highest point is found at ...
x = -(3.2)/(2(-0.15)) = 32/3 = 10 2/3 . . . . feet horizontally from the club
The maximum height is the function value at that point.
h(10 2/3) = (-0.15(10 2/3) +3.2)(10 2/3) = 1.6(10 2/3) = 17 1/15
The ball reaches a maximum height of 17 1/15 feet at a horizontal distance of 10 2/3 feet from the club. The ball's flight is symmetrical about the peak, so it returns to the ground about 21 1/3 feet away.
Find the next term in the sequence 3, 6, 9, 15, 24,
Lily has 3 dog toys that are red. One fifth of all her dog toys are red. How many dog toys does Lily have? Complete the explanation. Please I need help!!!!
Answer:
she has 15 dog toys
Step-by-step explanation:
mutlipy 3 by five because the top number is one
Add 8/9+4/9 and Simplify the answer and write as a mixed number.
Answer:
1 1/3
Step-by-step explanation:
Answer:
12/9= 1 and 1/3
Step-by-step explanation:
number 10 step by step :(
What are the x- and y-intercepts of the line with
equation 4x + 5y = 40 ?
Answer:
x - intercept - ( 10 , 0)
y - intercept - (0 , 8)
Step-by-step explanation:
Please help really quick
Answer:
88 yd.²
Hope this helps!
Answer:
Area= 88 sq. yd.
Step-by-step explanation:
The formula for the area of a triangle is A= h b/2.
This means you just divide 16 (the base) by 2 to get 8, and then multiply it by 11 (the height). This gives you 88
The radius of a circle is 18 inches. What is the circle's area?
Answer:
1017.88 inches
Step-by-step explanation:
Area = πr2 = π x 182 ≈ 1017.87602
What is the mode of the data set?
A. 90
B. No mode
C. 85.5
D. 49
Hurry and give a SERIOUS answer! Will give brainliest.
Answer:
mode is the number listed most often and data can have more then 1 mode
the numbers most listed in the image are: 5 and zero
Step-by-step explanation:
I hope this helped!
Answer:
90
Step-by-step explanation:
mode = A number that appears most often is the mode.
500 people were surveyed about their favorite type of pet. 55% of the people said
"dog", 1/10 said "cat", 0.3 said "bird", and the rest said "other". How many people
responded "other"?
Answer:
25/500 or 5% said 'other'
Step-by-step explanation:
55% = 275 (dog)
1/10 = 50 (cat)
0.3 = 150 (bird)
Total = 475
475 out of 500 (95%) gave an answer other than 'other'
Trinh is catering a wedding that 112 people will attend. She is making two cakes, a chocolate cake and a carrot cake. 0.625 of the guests will be served chocolate cake and the rest will receive carrot cake. How many guests will get carrot cake?
Answer:
Step-by-step explanation:
70
What is the volume please help me please
Answer:
1296(Length x Width x Height)
6x18x12=
1296I hope this helped! ♡+*
Find the area of the garden.
Answer:
28yd²
Step-by-step explanation:
area of square = side *side
=6*6= 36²
area of rectangle (patio)= length* breadth
=4*2=8²
area of garden= area of square - area of rectangle
=36-8
=28 yd²
Answer:
28 sq. ydStep-by-step explanation:
For finding the area of the garden :First Case:
Given,
Side of the big square = 6 yd
Therefore,
Area of the big square = side × side
= 6yd × 6yd
[tex] = 36 {yd}^{2} [/tex]
Second Case:
Length of the patio = 4 yd
Breadth of the patio = 2 yd
Therefore,
Area of the patio = Length × Breadth
= 4yd × 2yd
[tex] = 8 {yd}^{2} [/tex]
Last Case:
According to first and second cases,
Area of the garden
= Area of the big square - Area of the patio
[tex] = 36 {yd}^{2} - 8 {yd}^{2} [/tex]
[tex] = 28 {yd}^{2} [/tex]
Hence,Required area of the garden is 28 sq. yd (Ans)
The mean midday temperature recorded in June in a city in South California is 36ºC, and the standard deviation is 3ºC. The number of days in the month of June is 30.
Assuming the data is normally distributed, the number of days in June when the midday temperature was between 39ºC and 42ºC is .
Answer:
About 4 days
Step-by-step explanation:
Convert 39 and 42 degrees C to a z score and then use the z-table
The number of days in June when the midday temperature was between 39°C and 42°C is equal to 4.0 days.
Given the following data:
Mean midday temperature = 36°C.
Standard deviation = 3°C.
How to determine the number of days in June?In order to determine the number of days in June when the midday temperature was between 39°C and 42°C, we would determine the z-score as follows:
Let the midday temperature be M.
P(39 < M < 42) = 1 - [P(M < 39) + P(M < 42)]
Evaluating, we have:
P(M < 39) = P(Z < [39 -36/3])
P(M < 39) = P(Z < [3/3])
P(M < 39) = P(Z < 1).
P(M < 39) = 0.84134.
P(M < 42) = P(Z < [42 -36/3])
P(M < 42) = P(Z < [6/3])
P(M < 42) = P(Z < 2)
P(M < 42) = 0.02275.
Substituting the parameters into the formula, we have;
P(39 < M < 42) = 1 - [P(M < 39) + P(M < 42)]
P(39 < M < 42) = 1 - [0.84134 + 0.02275]
P(39 < M < 42) = 1 - 0.86409
P(39 < M < 42) = 0.13591.
Now, we can determine the number of days in June when the midday temperature was between 39°C and 42°C:
No. of days = 0.13591 × 30
No. of days = 4.0 days.
Note: There are 30 days in the month of June.
Read more on z-scores here: https://brainly.com/question/4302527
#SPJ2
Answer now please ♀️
Answer:
8/15
Step-by-step explanation:
In a right triangle, where B is an acute angle, the tan B is equal to the measure of the side opposite B divided by the measure of the shorter side at B
tanB = 16/30 = 8/15
Aling Nora bought 15 kilos of beef worth 1,845. How much is a kilo oof beef?
Answer:
1845/15=123
Step-by-step explanation:
Step-by-step explanation:
I don't now just paiattention to the problem that willed be more like it thx
How many integers between 0 and 500:
1. Have distinct digits?
2. Are divisible by 3?
3. Are divisible by 3 or 5?
4. Are divisible by either 3 or 5, but not both?
5. Are divisible by 3, but not 5?
Pls help asap!!
Answer:
4
Step-by-step explanation:
they are divisible by either 3 or 5 but not both of these numbers
Answer:
378
Step-by-step explanation:
1 digit numbers - 9
2 digit numbers - 90
Now, subtract the repeating numbers 90-9 = 81
3 digit numbers = 4*9*8 = 288
Distinct numbers = 9+81+288 = 378 numbers
Kei buys a table and 12 chairs. Each chair cost the same price. The table cost $165. The total cost for the table and 12 chairs is $ 465. What is the cost of one chair?
Answer:
[tex]165 + 12c = 465[/tex]
Is the right answer
Answer:$25 per chair
Step-by-step explanation:
It’s $165 for only the table. Minus that from the $465 and you get $300. Do $300 divided by 12(amount of chairs) And you get $25. It’s $25 per 1 chair.
Factor x2+4x+3.
O A. (x-3)(x+1)
O B. (x-3)(x-1)
O C. (x+3)(x+1)
O D. (x+3)(x-1)
QUICKKKKKKKK!!!!
Answer:
c. (x +3)(x + 1)
Step-by-step explanation:
Factoring an equation is a way of expressing an equation as the product of other linear expressions. The following expression,
[tex]x^2 +4x +3[/tex]
Can be represented as the product of the following,
[tex](x+3)(x+1)[/tex]
To check this, one can distribute, one of the expressions over the other, then simplify, the result should be the starting expression,
[tex](x+3)(x+1)\\[/tex]
Distribute,
[tex](x)(x)+(1)(x)+(3)(x)+(3)(1)[/tex]
Simplify,
[tex]x^2 +x +3x + 3\\[/tex]
[tex]x^2 +4x +3[/tex]
Which are undefined terms that can be used to define other terms?
O point, segment, ray
O point, line, plane
O line, plane, cube
O line, ray, angle
Answer:
Point, Line, Plane
Step-by-step explanation: They are undefined terms because its is easier to define them using examples rather than word for word
f(x) = 4x3 + 5x2 – 3x – 6
g(x) = 4x – 5
Find (f - g)(x).
Answer: soo
(4x^3+5x^2-3x-6)-(4x-5)
the answer is 4-^3+5x^2-7x-1
Step-by-step explanation:
This figure was broken into a triangle and a parallelogram as shown. Use the figures to complete the statements. The height of the triangle his in. The area of the triangle is vin.? The area of the parallelogram is in. 2 ? The area of the irregular figure is in. 2. ? h 22 in. 8 in. 10 in. Nin. 8 in. 8 in.
Answer: Use the figures to complete the statements.
The height of the triangle h is
✔ 12
in.
The area of the triangle is
✔ 48
in.2.
The area of the parallelogram is
✔ 80
in.2.
The area of the irregular figure is
✔ 128
in.2.
Step-by-step explanation: I js now got it right by the power of guessing
what does 5 × 100 equal
Answer: 500.
Step-by-step explanation:
Your answer is 500.
Bruce collects coins. He collected a total of 125 coins. If 68% of the coins he collected were foreign,
how many other coins did he collect?
Bruce collected coins that were not foreign.
(Type a whole number.)
Answer:
40
Step-by-step explanation:
100 - 68 = 32
32/100 = ?/125
125 x 32 = 4,000
4,000 ÷ 100 = 40
40% of 500 multiplying with decimal
Answer:
200
Step-by-step explanation:
First we need to find the decimal version of 40%
to do this we can move the decimal point 2 spaces to the left.
40% ---> 0.40
then we can multiply by 500
This is equal to 200
Answer: 200
Step-by-step explanation: 40%=.40
500•.4=200