answer.
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
crimeas [40]
2 years ago
13

A major department store chain is interested in estimating the mean amount its credit card customers spent on their first visit

to the chain's new store in the mall. Fifteen credit card accounts were randomly sampled and analyzed with the following results: = $50.50 and S = 20. Construct a 95% confidence interval for the mean amount its credit card customers spent on their first visit to the chain's new store in the mall assuming that the amount spent follows a normal distribution. A) $50.50 ± $9.09 B) $50.50 ± $10.12 C) $50.50 ± $11.00 D) $50.50 ± $11.08
Mathematics
1 answer:
viva [34]2 years ago
5 0

Answer: D) \$50\pm\$11.08

Step-by-step explanation:

As per given , we have

Sample size : n= 15

sample mean : \overline{x}=\$50.50

Sample standard deviation: s= $20

Since population standard deviation is unknown , so we use t-test.

Significance level for 95% confidence : \alpha=1-0.95=0.05

Critical t-value : t_{n-1, \alpha/2}=t_{014,0.025}=2.145  [Using students' t-value table]

Required 95% Confidence interval :-

\overline{x}\pm t_{n-1, \alpha/2}\dfrac{s}{\sqrt{n}}\\\\ =\$50.50\pm(2.145)\dfrac{\$20}{\sqrt{15}}\\\\\approx \$50\pm\$11.08

Hence, the required 95% confidence interval for the mean amount its credit card customers spent on their first visit to the chain's new store in the mall assuming that the amount spent follows a normal distribution.:

\$50\pm\$11.08

You might be interested in
What is the completely factored form of p4 - 16?
il63 [147K]

The completely factored form of p^4-16 is:

(p^2+4)(p+2)(p-2)

Step-by-step explanation:

We have to factorize the given expression to get the final result

Given

p^4-16\\Using\ Formula: a^2-b^2=(a+b)(a-b)\\(p^2)^2-(4)^2\\=(p^2+4)(p^2-4)

p^2-4 can further be factored again

=(p^2+4)[(p)^2-(2)^2]\\=(p^2+4)(p+2)(p-2)

The completely factored form of p^4-16 is:

(p^2+4)(p+2)(p-2)

Keywords: Factorization

Learn more about factorization at:

  • brainly.com/question/9323337
  • brainly.com/question/9381080

#LearnwithBrainly

8 0
2 years ago
The transportation department has to put a railing along the outer curve of this road. The road is 20 feet wide. What is the len
Dovator [93]
From my research, the image attached supports the problem. Since only the outer curve is to be solved for, the formula for arcs can be used.

s = theta*radius

where s = arc length = outer curve

theta = 70 (pi/180)
radius = 70

s = 70 * (70*pi/180)
s = 85.52 feet

Therefore, the outer curve is 85.52 feet long

6 0
2 years ago
Read 2 more answers
In addition to the facts in the diagram, which other statements are necessary to prove that ∆ABC is congruent to ∆EFG by the ASA
insens350 [35]

It should be B because you have to have 2 angles to know for sure.

8 0
2 years ago
Read 2 more answers
Of the 2000 students attending, every 5th student going into the basketball game is asked if the school should spend more money
MA_775_DIABLO [31]
The students would show no regard for the money being spent because it is not their money
8 0
2 years ago
Solve the inequalities for x, and match each solution to its number line graph.Two less than 3/2 of a number (x) is no more than
melamori03 [73]
I do not understand your question please explain further for me to answer
8 0
2 years ago
Read 2 more answers
Other questions:
  • What are the solutions of 8x2 = 6 + 22x? Check all of the boxes that apply.
    14·2 answers
  • A random group of high school and college students were asked if they study with or without listening to music. The frequency ta
    15·2 answers
  • Find the equation of the surface. a standard cone with vertex at (6, 0 , 0) opening up on the positive x-axis.
    5·1 answer
  • In Amy's garden the ratio of herbs to plants is 5:2. If there are 40 herb plants, how many vegetable plants are in her garden?
    12·1 answer
  • A 60-kg skier starts from rest from the top of a 50-m high slope. If the work done by friction is -6.0 kJ, what is the speed of
    15·1 answer
  • Last week, burton paid $36.80 for 11 1/2 gallons of gas this week he bought 9 1/4 gallons of gas. The cost per gallon of gas inc
    15·2 answers
  • HURRY I NEED HELP I'LL GIVE OUT THAT BRAIN THING
    10·1 answer
  • Serena is hitting golf balls at the driving range. When she hit a ball with her 9-iron, it stopped x yards in front of the 100-y
    13·2 answers
  • The vertex form of the equation of a vertical parabola is given by y= 1/4p(x-h)^2 , where (h, k) is the vertex of the parabola a
    14·1 answer
  • Jenna’s method: Mia’s method: 5(30 + 4) 5(30 + 4) (5)(30) + (5)(4) 5(34) = 170 150 + 20 = 170 Explain why both Jenna and Mia arr
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!