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
olasank [31]
3 years ago
11

A random sample of 50 cars in the drive-thru of a popular fast food restaurant revealed an average bill of $18.21 per car. The p

opulation standard deviation is $5.92. Round your answers to two decimal places.
(a) State the point estimate for the population mean cost of fast food bills at this restaurant $

(b) Calculate the 95% margin of error. $

(c) State the 95% confidence interval for the population mean cost of fast food bills at this restaurant. $ ≤ µ ≤ $

(d) What sample size is needed if the error must not exceed $1.00? n =
Mathematics
1 answer:
mars1129 [50]3 years ago
5 0

Answer:

a) \bar{x} = 18.21

b) 1.64

c) (16.57,19.85)

d) The sample size must be 135 or greater if the error must not exceed $1.00.

Step-by-step explanation:

We are given the following information in the question:

Sample size, n = 50

Sample mean =   $18.21

population standard deviation = $5.92

a)  Point estimate for the population mean cost

\bar{x} = 18.21

b) Margin of error =

z_{critical}\displaystyle\frac{\sigma}{\sqrt{n}}

z_{critical}\text{ at}~\alpha_{0.05} = 1.96

Margin of error =  1.96\displaystyle\frac{5.92}{\sqrt{50}} = 1.64

c) 95% Confidence interval

\mu \pm z_{critical}\displaystyle\frac{\sigma}{\sqrt{n}}

Putting the values, we get,

18.21 \pm 1.64) = (16.57,19.85)

d) Marginal error less than $1.00

1.96\displaystyle\frac{\sigma}{\sqrt{n}} \leq 1\\\\\sqrt{n} \geq 1.96\times 5.92\\n \geq (11.6)^2\\n \geq 134.56 \approx 135

Thus, the sample size must be 135 or greater if the error must not exceed $1.00.

You might be interested in
Express the division expression as a fraction in simplest form. Then, rewrite the fraction as a mixed number.
Levart [38]
14/4 is simplified to 7/2 and as a mixed number it would be 3 1/2
6 0
3 years ago
Read 2 more answers
A man buys six books from the store and a preferred reader discount card for $20. Later that day, he goes and buys five more boo
amid [387]

Answer:

Step-by-step explanation: i think it would be 8.36

5 0
3 years ago
How do you find the unknown length for a special right angel
alukav5142 [94]

Answer: Pythagorean theroem

Step-by-step explanation:

The easiest method to use in terms of a missing side as long as you know at least two other variables whether its another side or angle

8 0
3 years ago
What's bigger 1.60 or 1.6
klio [65]
They are equivalent to each other
7 0
3 years ago
Read 2 more answers
What is the quotient of 5 2/3÷ 3/2<br>​
padilas [110]

Answer:

9/10

Step-by-step explanation:

First, the division of two fractions is the multiplication of the first fraction with the inverse of the second fraction. Then, we have:

3/5 ÷ 2/3 = 3/5 × 3/2

Multiplying the numerators and the denominators, then we have only one fraction.

3/5 × 3/2 = 9/10

Solving this division, we assume that the quotient is 0 and the remainder is 9, because the denominator is greater than the numerator.

5 0
3 years ago
Other questions:
  • A tortoise is walking in the desert. It walks for 3.75 meters at a speed of 3 meters per minute. For how many minutes does it wa
    12·1 answer
  • Find the slope of each function and determine which has the steeper slope.
    14·2 answers
  • 1.<br>Is 435 evenly divisible by 5?<br>Circle: Yes or No​
    13·2 answers
  • What is (4x+3)(x-7)=90
    11·2 answers
  • BRAINLIEST IF CORRECT
    6·2 answers
  • HeLP me ASAP PLEASE ASAP i will give 50 points for the right answer
    10·1 answer
  • You buy a pair of jeans for 25% markdown from $32.00. The sales tax is 6%. How much will you pay for the jeans?
    13·2 answers
  • Her pie plate is 9 inches across. What will the area of her pie be? Use 3.14 for pi.
    6·1 answer
  • HELP FAST HURRY FAST PLZ
    9·1 answer
  • What is the actual height of the building shown in the model?
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!