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3 years ago

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A researcher wants to obtain a sample of 25 teachers from a school district employing 400 teachers in 8 schools. Choose the BEST

method for doing this.
A) Select the teachers whose students have the highest grade point averages in the system.
B) Ask the principal of each school to choose 3 teachers, then select the 25th teacher randomly.
C) Randomly select 12 male teachers, 12 females, and then randomly select a 25th teacher of either sex.
D) From an alphabetized list, select a teacher randomly, then select every 16th teacher on the list until 25

2 answers:

lesantik [10]3 years ago

8 0

Answer:

D

Step-by-step explanation:

Took the test with that question, on U.S test Prep

kvasek [131]3 years ago

4 0

Answer:

A

Step-by-step explanation:

You might be interested in

Suppose the round-trip airfare between Philadelphia and Los Angeles a month before the departure date follows the normal probabi

QveST [7]

Answer:

52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this question, we have that:

$\mu = 387.20, \sigma = 68.50$

What is the probability that a randomly selected airfare between these two cities will be between $325 and $425?

This is the pvalue of Z when X = 425 subtracted by the pvalue of Z when X = 325. So

X = 425

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{425 - 387.20}{68.50}$

$Z = 0.55$

$Z = 0.55$ has a pvalue of 0.7088

X = 325

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{325 - 387.20}{68.50}$

$Z = -0.91$

$Z = -0.91$ has a pvalue of 0.1814

0.7088 - 0.1814 = 0.5274

52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425

7 0

2 years ago

Pls help I’ll do anything<br> Extra points

Lady bird [3.3K]

Just Try 84 Bro..............

7 0

3 years ago

the time required to assemble computers varies directly as the number of computers assembled and inversely as the number of work

olga2289 [7]

Answer:

16 hours

Step-by-step explanation:

let t be time, n the number of computers and w the number of workers, then

t = $\frac{kn}{w}$ ← k is the constant of variation

To find k use the condition n = 30, w = 6 and t = 10 , then

10 = $\frac{30k}{6}$ ( multiply both sides by 6 )

60 = 30k ( divide both sides by 30 )

2 = k

t = $\frac{2n}{w}$ ← equation of variation

When w = 5 and n = 40 , then

t = $\frac{2(40)}{5}$ = $\frac{80}{5}$ = 16 hours

3 0

2 years ago

1. What is the solution of n² – 49 = 0? (1 point)

maks197457 [2]

Answer:

1. $n=\pm7$

2. $x=\pm7i[tex]3.[tex]\pm 12x =a$

4. 22

Step-by-step explanation:

1. $n^2 - 49 = 0$

$n^2 =49$

$n= \sqrt{49}$

$n=\pm7$

2. $x^2+64 = 0$

$x^2 =-64$

$x= \sqrt{49}$

$x=\pm7i[tex]3. Area of square = [tex]a^{2}$

Where a is the side

We are given an area o square = $144x^{2}$

So, $144x^{2}=a^{2}$

$\sqrt{144x^{2}}=a$

$\pm 12x =a$

4. We are given that the solution of quadratic equation -9 and 9

So, equation becomes:

$(x+9)(x-9)=0$

$x^2- 81=0$

So, in the given equation $x^2 + z = 103$

z should be the number from which if we subtract 103 so we get 81

Substitute z = 22

$x^2 + 22 = 103$

$x^2 + 22 -103=0$

$x^2 -81=0$

Thus the value of z is 22

8 0

3 years ago

Read 2 more answers

A string of decorative lights is 25 feet long. The first light on the string is 16 inches from the plug. The lights on the strin

joja [24]

25 feet = 25 x 12 = 300 inches

First light is at 16 inches.
300 - 16 = 284 inches

Find the rest of the bulbs:
284 ÷ 4 = 71

Total number of lights = 71 + 1 = 72

Answer 72 lights

8 0

3 years ago