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
just olya [345]
3 years ago
12

A box of tickets has an average of 420; the SD is 84. If we draw at random (with replacement) 50 times and compute the average o

f the draws, the expected value of the average of the draws equals 420 and the standard error of the average of the draws equals ____. (Enter correct to two decimal places.)
Mathematics
1 answer:
disa [49]3 years ago
4 0

Answer:

Average of the draws equals 420

Standard Error = 11.88

Step-by-step explanation:

Given

\mu = 420

\sigma = 84

n =50

Solving (a): The average of the draws

This implies that we calculate the sample mean

This is calculated as:

\bar x = \mu  --- Sample Mean = Population Mean

So, we have:

\bar x = 420

Solving (b): The standard error

This is calculated as:

SE=\frac{\sigma}{\sqrt n}

So, we have:

SE=\frac{84}{\sqrt {50}}

Using the calculator, we have:

SE=11.88

You might be interested in
If dx - 2 = h then x is equal to
Hatshy [7]
Yo idk maybe ask your teacher for help
6 0
3 years ago
Read 2 more answers
A certain railway company claims that its trains run late 5 minutes on the average. The actual times (minutes) that 10 randomly
iragen [17]

Answer:

Option C)  We would reject the claim that the trains run late an average of 5 minutes and conclude that they run late an average of more than 5 minutes since the 99% confidence interval exceeds 5.

Step-by-step explanation:

We are given the following in the question:  

Population mean, μ = 5 minutes

Sample mean, \bar{x} = 9.130 minutes

Sample size, n = 10

Alpha, α = 0.01

Sample standard deviation, s = 1.4 minutes

First, we design the null and the alternate hypothesis

H_{0}: \mu = 5\text{ minutes}\\H_A: \mu \neq 5\text{ minutes}

We have to construct 99% confidence interval.

99% Confidence interval:  

\bar{x} \pm t_{critical}\displaystyle\frac{s}{\sqrt{n}}  

Putting the values, we get,  

t_{critical}\text{ at degree of freedom 9 and}~\alpha_{0.01} = \pm 3.249  

9.130 \pm 3.249(\dfrac{1.4}{\sqrt{10}} ) = 9.130 \pm 1.4383 = (7.6917,10.5683)

99% Confidence interval:  (7.6917,10.5683)

Since the population mean does not lie in he calculated confidence interval, thus, we fail to accept the null hypothesis and accept the alternate hypothesis.

Option C) We would reject the claim that the trains run late an average of 5 minutes and conclude that they run late an average of more than 5 minutes since the 99% confidence interval exceeds 5.

6 0
3 years ago
Whats 7n + 4n + 5 HELP ME PLZZ
My name is Ann [436]
It can only be simplified unless n is defined.
7n + 4n + 5 = 11n + 5
8 0
3 years ago
Read 2 more answers
The town park is a rectangular strip of land with a width of 1/2 mile and an area of 1/8 square mile. How long is the town park?
weeeeeb [17]

Answer:

that would be 4/13

Step-by-step explanation:

i think

3 0
3 years ago
Read 2 more answers
Factor completely 9r^3-72r^2
PtichkaEL [24]

Answer:

9r²(r - 8)

Step-by-step explanation:

Step 1: Write expression

9r³ - 72r²

Step 2: Factor out 9

9(r³ - 8r²)

Step 3: Factor out r²

9r²(r - 8)

6 0
3 years ago
Other questions:
  • 6 - 8x = 6x - 9x + 11
    12·2 answers
  • A function for the cost of renting a snow blower is $13.50 per hour.
    13·1 answer
  • Sunny earns \$12$12 per hour delivering cakes. She worked for xx hours this week. Unfortunately, she was charged \$15$15 for a l
    13·2 answers
  • Dr. Kang, a cognitive psychologist, conducts an experiment examining the effect of emotion on memory. He provides lists of 15 wo
    14·1 answer
  • Angle 1 and 2 are complementary <br> angle 1 =x<br> angle2 = (3x+30)
    5·1 answer
  • Consider U = {x|x is a real number}.
    7·1 answer
  • I hate word problems XD so can you do this?<br> :]
    5·2 answers
  • Like for like ? follow for follow ?
    10·1 answer
  • Estimate 1<br> 9 1/3 divided by 3 2/3
    13·1 answer
  • At the beginning of each month, $200 is deposited into a retirement fund. The fund earns 6% annual interest, compounded monthly,
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!