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
Ludmilka [50]
3 years ago
10

A study of 138 penalty shots in World Cup Finals games between 1982 and 1994 found that the goalkeeper correctly guessed the dir

ection of the kick only 41% of the time. The article notes that this is "slightly worse than random chance." We use these data as a sample of all World Cup penalty shots ever. Test at a 5% significance level to see whether there is evidence that the percent guessed correctly is less than 50%. The sample size is large enough to use the normal distribution. The standard error from a randomization distribution under the null hypothesis is SE = 0.043. Let p represent the proportion of all World Cup penalty kicks for which the goalkeeper correctly guesses the direction of the kick.
a. State hypotheses in terms of a single proportion p.

b. Write the value of the sample statistic, using correct notation. Use the sample statistic and the standard error provided to calculate a z-statistic. Show your calculation.
Mathematics
1 answer:
vladimir2022 [97]3 years ago
4 0

Answer:

z=-2.09

Step-by-step explanation:

Given that a study  of 138 penalty shots in World Cup Finals games between 1982 and 1994 found that the goalkeeper correctly guessed the direction of the kick only 41% of the time.

Set up hypotheses as:

H_0: p=0.50\\H_a: p

(left tailed test at 5% significance level)

Standard error = 0.043

Sample proportion p = 0.41

p difference = 0.41-0.50=-0.09

Test statistic Z = p diff/std error

= \frac{-0.09}{0.043} \\=-2.09

Z = -2.09

You might be interested in
Sharon jarred 18 liters of jam after 9 days. How many days does Sharon need to spend making jam if she wants to jar 20 liters of
solong [7]

Answer:

40

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
PLS HELP! 7x +10y= -23<br><br> 7x + 6y = - 39
mote1985 [20]
4y = -23 + 39
4y = 16
y = 4

Sub y = 4 into equation 2
7x + 6(4) = -39
7x + 24 = -39
7x = -39-24
7x = -63
x = -9

x = -9
y = 4
5 0
2 years ago
A) f(x)<br> B) g(x)<br> C) h(x)
jeka57 [31]

Answer:

decreasing increasing decreasing function

3 0
3 years ago
Simplify the following fractions by putting them in lowest terms or by performing the indicated operations.
AleksAgata [21]
The answer is 9(3+x)
My work is in the attached image

3 0
3 years ago
Mathematical induction, prove the following two statements are true
adelina 88 [10]
Prove:
1+2\left(\frac12\right)+3\left(\frac12\right)^{2}+...+n\left(\frac12\right)^{n-1}=4-\dfrac{n+2}{2^{n-1}}
____________________________________________

Base Step: For n=1:
n\left(\frac12\right)^{n-1}=1\left(\frac12\right)^{0}=1
and
4-\dfrac{n+2}{2^{n-1}}=4-3=1
--------------------------------------------------------------------------

Induction Hypothesis: Assume true for n=k. Meaning:
1+2\left(\frac12\right)+3\left(\frac12\right)^{2}+...+k\left(\frac12\right)^{k-1}=4-\dfrac{k+2}{2^{k-1}}
assumed to be true.

--------------------------------------------------------------------------

Induction Step: For n=k+1:
1+2\left(\frac12\right)+3\left(\frac12\right)^{2}+...+k\left(\frac12\right)^{k-1}+(k+1)\left(\frac12\right)^{k}

by our Induction Hypothesis, we can replace every term in this summation (except the last term) with the right hand side of our assumption.
=4-\dfrac{k+2}{2^{k-1}}+(k+1)\left(\frac12\right)^{k}

From here, think about what you are trying to end up with.
For n=k+1, we WANT the formula to look like this:
1+2\left(\frac12\right)+...+k\left(\frac12\right)^{k-1}+(k+1)\left(\frac12\right)^{k}=4-\dfrac{(k+1)+2}{2^{(k+1)-1}}

That thing on the right hand side is what we're trying to end up with. So we need to do some clever Algebra.

Combine the (k+1) and 1/2, put the 2 in the bottom,
=4-\dfrac{k+2}{2^{k-1}}+\dfrac{(k+1)}{2^{k}}

We want to end up with a 2^k as our final denominator, so our middle term is missing a power of 2. Let's multiply top and bottom by 2,
=4+\dfrac{-2(k+2)}{2^{k}}+\dfrac{(k+1)}{2^{k}}

Distribute the -2 and combine the fractions together,
=4+\dfrac{-2k-4+(k+1)}{2^{k}}

Combine like-terms,
=4+\dfrac{-k-3}{2^{k}}

pull the negative back out,
=4-\dfrac{k+3}{2^{k}}

And ta-da! We've done it!
We can break apart the +3 into +1 and +2,
and the +0 in the bottom can be written as -1 and +1,
=4-\dfrac{(k+1)+2}{2^{(k-1)+1}}
3 0
3 years ago
Other questions:
  • The slope of MJ is –4, and MJ AP
    7·1 answer
  • A. How many lines of reflection symmetry does this shape have? (2 points)
    9·1 answer
  • ANSWER QUICK (30 POINTS) MUST BE RIGHT
    9·2 answers
  • John is putting money into his saving account. He starts with $350 in the savings account, and each week he adds 60$
    10·1 answer
  • A number y is at least 3 and is less than 10
    6·1 answer
  • The perimeter of a building is 900 feet. If the length of the building is 400 feet, find the width. How many lights will be need
    8·2 answers
  • A student is working two jobs over the summer to pay for a new car. The student gets paid $25 for each lawn that
    15·1 answer
  • Which of the following explains how to solve the problem below 1/8 divided 9
    14·2 answers
  • You open your first savings account three months ago so far you have earned 9.80 and simple interest at an annual interest rate
    15·1 answer
  • Find mBAF help ASAP.
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!