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
Write an expression that represents the volume of a rectangular-shaped box with a length 3 inches less than its height and a wid
slava [35]

Answer: h(h-3)(h+4)  

Step-by-step explanation:

To find the volume of rectangular-shaped box  we will have to multiply the length by the width by the height.

Given the statements  we can determine the  length with the equation

L = h -3  where l is the length and h is the height.

the width can also be represent by the equation

w = h + 4        

The height is is h and the length is h- 3  and the width is also h+4  so the expression will be    h(h-3)(h+4)

8 0
3 years ago
Please help me with this question If you don't know Please don't answer
Afina-wow [57]

Answer:

t squared over  9

Step-by-step explanation:

6 0
2 years ago
Read 2 more answers
Could you please help me? -0.7-(-2.5)=
Reika [66]
-0.7 - (-2.5) = 

-0.7 + 2.5 = 

2.5 - 0.7 = 1.8

1.8 is your answer

hope this helps
3 0
3 years ago
Functions! Help with number 3 please!!!
Norma-Jean [14]

Answer: 20

Step-by-step explanation:

Assuming g(x) = -4x + 1,

( -4 (-4) + 1) - (-4 + 1)

= (16 + 1) - (-3)
= 17 + 3

= 20

3 0
2 years ago
Solve the equation. Show all work.<br> -2 (4 - x) = 12x – 3<br> (I think this is 9th grade algebra)
Genrish500 [490]

Answer:

-1/2

Step-by-step explanation:

-2 (4 - x) = 12x – 3

-8+2x=12x-3

+8            +8

2x=12x+5

-12x  -12x

-10x=5

/-10  /-10

= -1/2

4 0
3 years ago
Read 2 more answers
Other questions:
  • What angle measures 3 degree
    7·2 answers
  • PQR is a right angled triangle with angle R 90 According to Pythagoras rule​
    5·1 answer
  • What does it mean to draw a model for 8/10
    9·1 answer
  • Find the derivative of f(x) = negative 6 divided by x at x = 12.
    6·2 answers
  • Greg has 25 tokens for the subway. He uses three tokens each week. How many weeks can he use the subway before he has to buy mor
    5·1 answer
  • Here is a square inscribed in a circle with radius 1 meter. What is the perimeter of
    9·1 answer
  • Mae Ling earns a weekly salary of $380 plus a 8.0% commission on sales at a gift shop. How much would she make in a work week if
    5·1 answer
  • Find three consecutive integers whose sum of the first and the third is -88
    15·1 answer
  • 25 points
    14·2 answers
  • Surface area of cone below diameter AB is 20 and distance from B to C is 10
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!