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
-Dominant- [34]
3 years ago
12

An article claims that 12% of trees are infested by a bark beetle. A random sample of 1,000 trees were tested for traces of the

infestation and found that 127 trees were affected.
z = p - p/underroot pq/n
Using the formula and data provided, what is the value of the z-test statistic?
Mathematics
1 answer:
galben [10]3 years ago
6 0

Answer:

0.68

Step-by-step explanation:

The formula for z test is given above as:

z = p' - p/√(pq/n)

p' = sample proportion

= Number of infested samples(trees)/ Number of samples

p' = 127/1000 = 0.127

p = 12% = 0.12

q= 1 - 0.12 = 0.88

n = number of samples = 1000

z = 0.127 - 0.12/√(0.88 × 0.12/1000)

z = 0.007/√0.0001056

z = 0.007 /0.0102761861

z = 0.6811865737

Therefore, the z test statistic is approximately ≈ 0.68

You might be interested in
What is the process of changing from one form to another
nasty-shy [4]

Answer:

it is transformation

4 0
3 years ago
Read 2 more answers
A tennis player keeps track of the number of successful first serves he makes. During the first 8 service points of a game, only
Andru [333]

Answer:

He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.

Step-by-step explanation:

After n consecutive serves, his total number of serves is going to be n+8, since he has already served 8 times. In the best case, his number of successful first serves is n+2.

His percentage of succesful first serves is the division of the number of succesful first serves divided by the total number of serves. So

P = \frac{n+2}{n+8}

We want P = 0.60. So

0.6 = \frac{n+2}{n+8}

n+2 = 0.6*(n+8)

n + 2 = 0.6n + 4.8

n - 0.6n = 4.8 - 2

0.4n = 2.8

n = \frac{2.8}{0.4}

n = 7

He needs 7 more consecutive successful first serves to raise his first serve percentage to 60%.

5 0
3 years ago
Simplify this expression.<br> 2x/12(x + y)
Ymorist [56]

Answer: = 1 /6 x^2+ 1 /6 xy

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
Describe two different ways that you could find the product 8 x 997 using mental math. Find the product and explain why your met
jolli1 [7]
One method is to round 997 up to 1000, multiply by 8, and then subtract 8 times 3. This would give you the solution of 7976.

Another method (Which I personally wouldn't use) is to recursively double 997. This is more difficult, although effective. After you double 997, double the resulting number, and then double the resulting number from that, you have the solution. This is because 2^3 is 8. 
5 0
3 years ago
Which expression is equivalent to ? Assume
stepan [7]

Answer:

b/a

Step-by-step explanation:

Given,(b^-2)/a*(b^-3)

or,(b^-2+3)/a

or,b/a

7 0
3 years ago
Read 2 more answers
Other questions:
  • which undefined geometric term is described as an infinite set of points that has length but not a width
    11·1 answer
  • Help please!!
    8·2 answers
  • What is the approximate total length of iron edging needed to create the square frame and the two diagonals
    9·1 answer
  • What is the domain and range?
    8·1 answer
  • Country Workshop manufactures both finished and unfinished furniture for the home. The estimated quantities demanded each week o
    7·1 answer
  • How do you solve this equation and what is the answer?
    5·2 answers
  • The sum of 3 consecutive even number is 270<br>what is thr first number in this sequense​
    6·1 answer
  • The local ice cream shop surveyed the customers to see which flavor of ice cream is most popular 125 people choose chocolate as
    6·1 answer
  • A pair of earrings cost 25000 Indonesian rupiah. the conversion rate is
    14·1 answer
  • The length of a rectangular garden is 30 yards more than the width. The perimeter is 300 yards. Find the length and width
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!