A department store buys 300 shirts for a total cost of $7,200 and sells them for $30 each. Find the percent makeup.

Among 320 randomly selected airline travelers, the mean number of hours spent travelling per year is 24 hours and the standard d

Ostrovityanka [42]

The margin of error of the random selection is 0.29

The given parameters are:

$n = 320$ --- the sample size

$\sigma = 2.9$ --- the standard deviation

$\bar x = 24$ --- the mean

$\alpha = 90\%$ --- the confidence level.

The margin of error (E) is calculated as follows:

$E = z \times \sqrt{\frac{\sigma^2}{n}}$

So, we have:

$E = z \times \sqrt{\frac{3.2^2}{320}}$

$E = z \times \sqrt{\frac{10.24}{320}}$

The z-value for 90% confidence level is 1.645.

Substitute 1.645 for z

$E = 1.645 \times \sqrt{\frac{10.24}{320}}$

$E = 1.645 \times \sqrt{0.032}$

Take square roots

$E = 1.645 \times 0.1789$

Multiply

$E = 0.2943$

Approximate

$E = 0.29$

Hence, the margin of error is 0.29

Read more about margin of error at:

brainly.com/question/14396648

5 0

2 years ago

Read 2 more answers

To clear both of the fractions from fox + 7 = 5 – x, we can multiply both sides of

tatyana61 [14]

Answer:

6,10,or 30 is your answer

3 0

3 years ago

What is the slope of the line that passes through these two points?

Montano1993 [528]

Answer:

slope of the line is 0

Step-by-step explanation:

given points are:

(-3 , 2)=(x1 , y1)

(4 , 2)=(x2 , y2)

slope =y2 - y1/x2 - x1

=2-2/4-(-3)

=0/4+3

=0/7

=0

4 0

2 years ago

Conduct the appropriate hypothesis test and compute the test statistic. A company that produces fishing line undergoes random te

andre [41]

Answer:

Option D) Yes, because the test statistic is -2.01

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 30 pound

Sample mean, $\bar{x}$ = 29.1 pounds

Sample size, n = 20

Alpha, α = 0.05

Sample standard deviation, s = 2 pounds

First, we design the null and the alternate hypothesis

$H_{0}: \mu = 30\text{ pounds}\\H_A: \mu < 30\text{ pounds}$

We use one-tailed(left) t test to perform this hypothesis.

Formula:

$t_{stat} = \displaystyle\frac{\bar{x} - \mu}{\frac{\sigma}{\sqrt{n}} }$

Putting all the values, we have

$t_{stat} = \displaystyle\frac{29.1 - 30}{\frac{2}{\sqrt{20}} } = -2.012$

Now,

$t_{critical} \text{ at 0.05 level of significance, 19 degree of freedom } = -1.729$

Since,

$t_{stat} < t_{critical}$

We fail to accept the null hypothesis and reject it. We accept the alternate hypothesis. Thus, there were enough evidence to conclude that the fishing line breaks with an average force of less than 30 pounds.

Option D) Yes, because the test statistic is -2.01

5 0

3 years ago

What is the equation of the axis of symmetry for the parabola y= 1/4(x+2)^2-7

Nezavi [6.7K]

Your answer is -2 as the axis of symmetry is at -b/2a. So if you were to expand the equation, you would get y= x^2/4 +x -6 where b is 1 and 2a is ½ . Therefore -1 / ½ gives you -2

7 0

3 years ago

A department store buys 300 shirts for a total cost of $7,200 and sells them for $30 each. Find the percent makeup.​

A department store buys 300 shirts for a total cost of $7,200 and sells them for $30 each. Find the percent makeup.