1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Alex17521 [72]
2 years ago
7

e 400 trials in which the assistant maintained a neutral expression, the driver stopped in 229 out of the 400 trials. Find a 95%

confidence interval for the proportion of drivers who would stop when a neutral expression is maintained. In the 400 trials in which the assistant smiled at the driver, the driver stopped in 277 out of the 400 trials. Find a 95% confidence interval for the proportion of drivers who would stop when the assistant is smiling. What do your results in parts (a) and (b) suggest about the effect of a smile on a driver stopping at a pedestrian crosswalk? Explain briefly. (In Chapter 23, we will consider formal methods for comparing two proportions.)
Mathematics
1 answer:
Fittoniya [83]2 years ago
6 0

Answer:

Step-by-step explanation:

n = 400

Proportion p = 229/400= 0.5725

For 95% confidence interval we use Z value as 1.96

Std error = 0.025

margin of error = 1.96*0.025

Confidence interval 95% = 0.5725±Margin of error

= (0.524, 0.621)

b) When smiled x becomes 277

p = 0.6925

Std error = 0.023

Margin of error= 1.96*0.023

Confidence interval = (0.647, 0.738)

Smiling increases the chances of stopping since mean and conidence interval bounds are showing increasing trend.

You might be interested in
Please help!!! Mark is learning to snowboard. The club charges $10 per hour for snowboard lessons and $40 for the lift ticket an
sveta [45]
H represents the number of hours:
10h + 40
(40 represents, well $40)
4 0
3 years ago
Read 2 more answers
if a square has an area of 255 square yards and a perimeter of 60 yards what is the side length of the square
Marta_Voda [28]

Answer: 15, if area is supposed to be 225

Step-by-step explanation:

60 / 4 sides = 15

15*15= 225

8 0
3 years ago
Find the area of the
Alex73 [517]

162 m^2

you can make a triangle in the corner with legs length s/2 and the angles are 45 degrees. in a 45 45 90 triangle, the legs are h/sqrt(2) where h is the hypotenuse. this means that s/2=9/2 sqrt(2), s=9 sqrt(2)

and s^2=162

5 0
3 years ago
The prism has a volume of 120 cm3. What would the volume of the prism be if each dimension were halved? cm3 Triangular prism wit
Citrus2011 [14]
The volume of a triangular prism is V = 1/2 x a x c x h where a is height of the triangle, c is the base of the triangle and h is the height of the prism.
120 = 1/2 x a x c x h; we write a from the previous equation in terms of c and h thus,
a = 240 / ( c x h)
If the dimensions where halved then a = a/2 ; c = c/2 ; h=h/2
We use the volume formula again and substitute the given values to find the new volume,
V = 1/2 x a/2 x c/2 x h/2
Substitute the previously determined a term,
V = 1/2 x (240/2ch) x c/2 x h/2
We cancel and evaluate the constants therefore the new volume is,
V= 15 cm^3
3 0
3 years ago
A pack of 5 book costs $18.75. A pack of 3 books $12.75. Which pack has the the lowest cost per books (hint - find the unit rate
vredina [299]
18.75÷5=3.75
12.75÷3=4.2
The pack of 5 books has the lower cost per book
4 0
2 years ago
Other questions:
  • Help me with this one question plz i put a picture below so u can see it
    15·1 answer
  • Which equation could represent "the area of a square as a function of a side"?
    9·1 answer
  • The graph shows Allison distance as she swam during her swim practice. What does point a tell you?
    12·1 answer
  • Which is bigger 3/4 or 2/3
    11·2 answers
  • Keith bake 3 cherry pies and 2 apple pies.He wants to share each pie equally among 6 of his neighbors. How much of each type of
    7·1 answer
  • The coordinates A(0,0) B(0,4) and C(2,0)are graphed and connected together. What 3 dimensional shape will be created
    6·1 answer
  • Emergency, pls answerrrrr
    6·2 answers
  • What is the interquartile range for the set of data?
    6·1 answer
  • Solve 3 - x/2 > 15..
    11·2 answers
  • Which equation is shown in the graph?<br><br> Best answer gets brainliest!
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!