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Nat2105 [25]
3 years ago
8

Police departments use exams as part of their promotion process and officers have to score higher than 80% of those taking the t

est to be considered for promotion. Officer #1 receives a raw score of 74 and Officer #2 receives a raw score of 68. The mean of all the exam scores is 65 with a standard deviation of 9. 1) Calculate the z score for Officer #1. Will he be promoted? 2) Calculate the z score for Officer #2. Will she be promoted? Please give the z score for each officer's exam and the result
Mathematics
1 answer:
Rashid [163]3 years ago
4 0

Answer:

z score for officer1 is 1, he will be promoted.

z score for officer2 is 0.33, she will not be promoted.

Step-by-step explanation:

Officer 1 get 74 points. O1=74

Officer 2 get 68 points. O2=68

Mean of the exam is 65 and standart deviation is 9 . M=65 and s=9

1) z-score for O1 can be found using the formula:

\frac{74-65}{9} =1

2) z-score of O2 is

\frac{68-65}{9} =0.33

Promotion is gained if an officer (O), scores higher than 80% of the officers taking the exam. This means they need to be at least in the top 20% of the exam. Therefore we look for the corresponding z score for the P(z)=0.2 which is 0.8416. Since z-score of O1 is bigger that 0.8416, he promotes. Officer2 who got 68 from the exam cannot promote since corresponding z-score is less than 0.8416

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I need help with 25 and 26 plzz
Paha777 [63]

Answer:

Step-by-step explanation:

25.

Combine like terms.

4t+7=-33

subtract 7 from both sides

4t=-40

divide both sides by 4

t=-10

26.

Subtract 2a from both sides

5=7a-16

add 16 to both sides

21=7a

divideby 7 on both sides

a = 3

I'd suggest getting the app photomath or using cymath to help you with these problems. they give you the answer and how to get it step by step

8 0
3 years ago
Bo and Erica are yoga instructors. Between the two of them, they teach 45 yoga classes each week. If Erica teaches 15 fewer than
Solnce55 [7]

Answer:

20 and 25.

Step-by-step explanation:

Given:

They both teach total 45 yoga classes each week.

Erica teaches 15 fewer than twice as many as Bo.

To find:

How many classes does each instructor teach per week  = ?

Solution:

Let number of classes are taken by Bo = x

Then number of classes are taken by Erica = 2x - 15  (given)

Total number of classes are taken by both = 45           (given)

According to the question.

x + 2x - 15 = 45

3x - 15 = 45

By adding both side by 15

3x = 60\\

By dividing both side by 3

x = 20

number of classes are taken by Bo = x = 20

number of classes are taken by Erica = 2x - 15

                                                               = 2\times20 - 15 = 40- 15 = 25\\

Therefore, number of classes are taken by Bo and  Erica is 20 and 25.

6 0
3 years ago
What does x is greater than 5 mean
kotegsom [21]

Answer:

That  x is any number  bigger that 5 so 6 plus

Step-by-step explanation:

3 0
3 years ago
In the 1980’s, a clinical trial was conducted to determine if taking an aspirin daily reduced the incidence of heart attacks. Of
zubka84 [21]

There is enough evidence to conclude that taking aspirin cannot  reduces the chance of cancer.

Given sample size of patients take aspirin 11037, sample size of patients who have assigned placebo group be 11034. 104 doctors who take aspirin had a heart attack, 189 doctors had placebo had heart attacks.

First we have to form hypothesis.

H_{0} :p{1} -p_{2} =0

H_{1}:p_{1} -p_{2} < 0

We have to find the respective probabilities.

p_{1}=104/11037

=0.0094

p_{2}=189/11034

=0.0171

Now their respective margin of errors.

s_{1}=\sqrt{ {(0.0094*0.9906)/11037}

=0.0009

s_{2}=\sqrt{0.0171*0.9829}

=0.0011

Hence the distribution of the differences,they are given by:

p=p_{1} -p_{2}

=0.0094-0.0171

=-0.0077

S=\sqrt{s_{1} ^{2}+s_{2} ^{2}  }

=\sqrt{(0.0009)^{2} +(0.0011)^{2} }

=0.00305

z=(p -f)/S (In which f=0 is the value tested at the null hypothesis)

=(-0.0077-0)/0.00305

=-2.52

p value will be 0.005.

p value of 0.05 significance level.

z=1.96.

1.96>0.005

So we will reject the null hypothesis which means it cannot reduce the whole chance of becomming a heart attack.

Hence there is enough evidence to conclude that taking aspirin cannot  reduces the chance of cancer.

Learn more about t test at brainly.com/question/6589776

#SPJ4

6 0
2 years ago
HELP!!!!! <br> answer asap! this is due in two hours!!
lapo4ka [179]

Answer:

it is 56

Step-by-step explanation:

there are 4 sides and they are all 10 and if you add them they are 40 and if you do the bottom it is 16 and 40 + 16 is 56  hope it helps

5 0
3 years ago
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