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
IceJOKER
2 months ago
13

To determine whether they need to hire extra help for the holiday season, the managers of a railroad company want to estimate ho

w long, on average, it takes a crew to unload a freight car at the Lafayette station. They will calculate an estimator as the sample mean of a random sample of unloading times. The managers want the sample mean to have a standard error of 1.51.5 minutes. The corporate office has provided a standard deviation of 99 minutes to use for calculation purposes. How large should the random sample be to ensure the sample mean has the desired standard error?
Mathematics
1 answer:
Svet_ta [12.7K]2 months ago
3 0
The answer is 36. Given data includes a standard error of 1.5 minutes and a standard deviation of 9 minutes. When working with sample size n, the standard error can be expressed as (standard deviation) ÷ √n. This means that 1.5 = 9 ÷ √n. Thus, √n equals 9 ÷ 1.5, which yields √n = 6. Consequently, squaring both sides provides n = 6², resulting in 36.
You might be interested in
A statistics professor at a large university hypothesizes that students who take statistics in the morning typically do better t
Svet_ta [12734]

Answer:

The resulting value is 2.381

Step-by-step explanation:

Using the information presented in the question, we will calculate the evidence supporting the professor's hypothesis

Given that:

x₁ = 74,

n₁ = 36

s₁ = 8

x₂ = 68

n₂ = 36

s₂ = 10

The hypotheses can be outlined as:

The critical value is t₃₆+₃₆-₂,₀.₀₁ = t₇₀,₀.₀₁

thus,

t₃₆+₃₆-₂,₀.₀₁ = t₇₀,₀.₀ = 2.381

This implies a range of -2.381 to 2.381

Thus, we can support the professor's assertion.

5 0
1 month ago
An artist can paint 4 painting in 2 hours. What is the artist’s unit rate?
AnnZ [12381]

To find the unit rate, we simply divide 4 by 2.

4 ÷ 2 = 2

This means the artist can complete 2 paintings every hour, establishing the unit rate as 2 paintings per hour.

Hope this assists

-AaronWiseIsBae

8 0
2 months ago
Read 2 more answers
Engineers measure angles in gradients, which are smaller than degrees. The table shows the conversion of some angle measures in
tester [12383]
The following table presents the conversion from degrees to gradients.

To calculate the slope, we take the difference between the two y-values (gradients) and divide it by the difference between the corresponding x-values (degrees).

For this purpose, we will use the initial and final points listed in the table. Therefore, the slope m is calculated as:

m= \frac{300-(-200)}{270-(-180)}  \\  \\ 
m= \frac{500}{450} \\  \\ 
m=1.11

After rounding to two decimal places, the slope of the line converting degrees to gradients is 1.11

8 0
3 months ago
Read 2 more answers
Solve for y 4.2x - 1.4y = 2.1
tester [12383]
4.2x - 1.4y = 2.1
-1.4y = 2.1 - 4.2x
y = \frac{2.1 - 4.2x}{-1.4}
y = 3x - 1.5 <==
3 0
3 months ago
Read 2 more answers
. Donny had a 10-foot board. He used the board to make two shelves. One shelf measured 4 feet 7 inches wide and the other shelf
tester [12383]
The length of the remaining piece measures 2 feet and 3 inches.
3 0
2 months ago
Other questions:
  • You randomly survey students about year-round school. The results are shown in the graph.
    7·1 answer
  • What is true about △ABC? Select three options
    9·2 answers
  • A store uses the expression –2p + 50 to model the number of backpacks it sells per day, where the price, p, can be anywhere from
    8·2 answers
  • What is the end behavior of the graph of the polynomial function f(x) = –x5 + 9x4 – 18x3?
    8·2 answers
  • Sue's tyre pressure gauge shows a reading which is 8% higher than the actual pressure.
    10·1 answer
  • A machine assembly requires two pyramid-shaped parts. One of the pyramids has the dimensions shown in the figure. The other pyra
    13·2 answers
  • Gus has a fish tank that holds 471047104710 inches^3 3 cubed of water. He is using a cylinder shaped bucket with a radius of 555
    11·1 answer
  • What is the following simplified product? Assume x greater-than-or-equal-to 0 (StartRoot 10 x Superscript 4 Baseline EndRoot min
    10·1 answer
  • Rachael’s employer matches 16% of Rachel’s contribution to her 401k plan. If racheals employer contributed $400 to the plan a ye
    10·2 answers
  • Which of the following predictions can be calculated using a geometric distribution?
    11·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!