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
gulaghasi [49]
3 years 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:
nadezda [96]3 years ago
3 0

Answer:

36

Step-by-step explanation:

Data provided in the question:

Standard error = 1.5 minutes             ( ∵ number are repetitive 1.51.5 )  

Standard deviation = 9 minutes        ( ∵ number are repetitive 99 )

Now,

Standard error = ( Standard deviation ) ÷ √n

Here,

n is the sample size

Therefore,

on substituting the respective values, we get

1.5 = 9 ÷ √n

or

√n = 9 ÷ 1.5

or

√n = 6

or

n = 6² = 36

You might be interested in
Line segment XY is tangent to circle Z at point U. Circle Z is shown. Line segment U V is a secant. Line segment X Y is a tangen
Yuri [45]

Answer:

138°

Step-by-step explanation:

∠YUV creates arc YV. Circle Z is made up of arc UV (84°) and arc YV. Solve for the measure of arc YV. (A circle equals 360°)

84° + x = 360°

arc YV = 276°

arc YV is formed from a secant and a tangent. Because of this ∠YUV is half of arc YV.

276° ÷ 2 = 138°

∠YUV = 138°

3 0
2 years ago
Read 2 more answers
If the output and input of a linear equation are proportional, where will the graph of the equation cross the x-axis?
mars1129 [50]

Answer:??? I don't know

Step-by-step explanation:

???

5 0
2 years ago
Solve by the addition method
Sladkaya [172]
Answer is no solution I believe
7 0
3 years ago
A theater has 56 rows of seats. If there are 13 seats in the first row, 18 in the 2nd row, 23 in the 3rd row. How many seats are
Anna35 [415]

Answer:

8428

Step-by-step explanation:

According to the Question,

  • Given, A theater has 56 rows of seats. If there are 13 seats in the first row, 18 in the 2nd row, 23 in the 3rd row.

We have a number sequence  13, 18, 23, ...

  • We can say that this is an arithmetic sequence because of the common difference 'd', is equal to 5, and the first term 'a1' is equal to 13.
  • The formula for the sum of an arithmetic sequence with n terms is given is S_n= \frac{n}{2} [2a_1+(n-1)d]S .

Substitute the given values into the equation to solve for the sum of the 56 rows of seats.

S_56= \frac{56}{2}[2(13)+(56-1)(5)]\\S_{56}=28\left[26+275\right]\\S_{56}=28\left[301\right]\\S_{56}=8428

Therefore, there are 8428 seats in all.

4 0
3 years ago
Susan's elevation at the top of a mountain is 1,530 meters. After 4 hours of climbing down her elevation is 680 meters. What is
Nitella [24]

Answer:

C) -212.5

Step-by-step explanation:

I've done this question on a quiz before.

Hope I helped!! :D

4 0
3 years ago
Other questions:
  • 3.2.AP-4
    8·1 answer
  • Model of how to find quotient 2.4 divided by 3
    15·1 answer
  • Math help please thanks :3
    14·1 answer
  • 36.00 with a 7% sales tax
    11·1 answer
  • Can u help me pls they are exponents with multiplication and division
    12·1 answer
  • Draw a rough sketch of the graph of f(x)=(x+1)^2(x-4). Insert a picture of your sketch below.
    15·1 answer
  • What is the image point of (0,-9)after a translation right 5 units and down 1 unit?
    10·1 answer
  • -10 + 10у + -3y +7<br> DOES ANYONE KNOW THE ANSWER????????????
    12·1 answer
  • Reciprocal of a number<br> 2/9......-7/6......8/3
    9·1 answer
  • Evaluate the function 2/3t , when t = 30.
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!