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Y_Kistochka [10]

2 years ago

6

Descriptive Measures Instructions: Use the following data set to find the sample statistics for the following data set. (Round a

nswers to the nearest hundredth, if necessary.
{51,48,42,43,48,48,46,15,29,45,47,55,46,35,47,48,54,26,53,42}

Find n

1 answer:

iren2701 [21]2 years ago

8 0

Answer:

(1) N or n = 20

(2) = 43.4

(3) σ = 9.78 and s = 10.04.

Step-by-step explanation:

You might be interested in

An economist uses the price of a gallon of milk as a measure of inflation. She finds that the average price is $3.82 per gallon

salantis [7]

Answer:

(a) The standard error of the mean in this experiment is $0.052.

(b) The probability that the sample mean is between $3.78 and $3.86 is 0.5587.

(c) The probability that the difference between the sample mean and the population mean is less than $0.01 is 0.5754.

(d) The likelihood that the sample mean is greater than $3.92 is 0.9726.

Step-by-step explanation:

According to the Central Limit Theorem if we have an unknown population with mean <em>μ</em> and standard deviation <em>σ</em> and appropriately huge random samples (<em>n</em> > 30) are selected from the population with replacement, then the distribution of the sample means will be approximately normally distributed.

Then, the mean of the distribution of sample mean is given by,

$\mu_{\bar x}=\mu$

And the standard deviation of the distribution of sample mean is given by,

$\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}$

The information provided is:

$n=40\\\mu=\$3.82\\\sigma=\$0.33$

As <em>n</em> = 40 > 30, the distribution of sample mean is $\bar X\sim N(3.82,\ 0.052^{2})$ .

(a)

The standard error is the standard deviation of the sampling distribution of sample mean.

Compute the standard deviation of the sampling distribution of sample mean as follows:

$\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}$

$=\frac{0.33}{\sqrt{40}}\\\\=0.052178\\\\\approx 0.052$

Thus, the standard error of the mean in this experiment is $0.052.

(b)

Compute the probability that the sample mean is between $3.78 and $3.86 as follows:

$P(3.78$

$=P(-0.77$

Thus, the probability that the sample mean is between $3.78 and $3.86 is 0.5587.

(c)

If the difference between the sample mean and the population mean is less than $0.01 then:

$\bar X-\mu_{\bar x}$

Compute the value of $P(\bar X$ as follows:

$P(\bar X$

$=P(Z$

Thus, the probability that the difference between the sample mean and the population mean is less than $0.01 is 0.5754.

(d)

Compute the probability that the sample mean is greater than $3.92 as follows:

$P(\bar X>3.92)=P(\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}>\frac{3.92-3.82}{0.052})$

$=P(Z$

Thus, the likelihood that the sample mean is greater than $3.92 is 0.9726.

3 0

3 years ago

a boy is standing on a pole of height 14.7m throws a stone upwards. it moves in a vertical line slightly away from the pole and

fomenos

Answer:

The time taken for the upward motion is 1 second. The same time is taken for the downward motion

It reaches a maximum height of 4.9 meters.

Step-by-step explanation:

The equation of motion is:

$x(t) = -4.9t^{2} + 9.8t$

Since the term which multiplies t squared is negative, the graph is concave down, that is, x increases until the vertex, where it reaches it's maximum height, then it decreases.

Vertex of a quadratic equation:

Quadratic equation in the format $x(t) = at^{2} + bt + c$

The vertex is the point $(t_{v}, x(t_{v}))$ , in which

$t_{v} = -\frac{b}{2a}$

In this question:

$x(t) = -4.9t^{2} + 9.8t$

So $a = -4.9, b = 9.8$

Vertex:

$t_{v} = -\frac{9.8}{2*(-4.9)} = 1$

The time taken for the upward motion is 1 second.

$x(t_{v}) = x(1) = 9.8*1 - 4.9*(1)^{2} = 4.9$

It reaches a maximum height of 4.9 meters.

Downward motion:

From the vertex to the ground.

The ground is t when x = 0. So

$-4.9t^{2} + 9.8t = 0$

$4.9t^{2} - 9.8t = 0$

$4.9t(t - 2) = 0$

$4.9t = 0$

$t = 0$

Or

$t - 2 = 0$

$t = 2$

It reaches the ground when t = 2 seconds.

The downward motion started at the vertex, when t = 1.

So the duration of the downward motion is 2 - 1 = 1 second.

5 0

3 years ago

36<br>48<br>Common Factors:<br>GCF:<br><br><br>What is it?

Lady_Fox [76]

Answer: 6

Step-by-step explanation: 36 divided by 6 equals 6

48 divided by8 is 6

common factor is 6

4 0

3 years ago

. The Empire State Building is a 102-story skyscraper. Its height is 1,250 ft. from the ground to the roof. The length and width

Aleks [24]

Answer: a) Dimensions of miniature is 0.17 × 0.08 × 0.5, b) 0.006 ft³.

Step-by-step explanation:

Since we have given that

Height of building = 1250 feet

Length of building = 424 ft

Width of building = 187 ft

Now, we know that The miniature version is just 1/ 2500 of the size of the original.

So, Height of miniature would be

$\dfrac{1250}{2500}=0.5\ ft$

Length of miniature would be

$\dfrac{424}{2500}=0.17\ ft$

Width of miniature would be

$\dfrac{187}{2500}=0.08\ ft$

a) What are the dimensions of the miniature Empire State Building?

Dimensions of miniature is 0.17 × 0.08 × 0.5

b. Determine the volume of the miniature building. Explain how you determined the volume.

$Volume=0.5\times 0.08\times 0.17=0.006\ ft^3$

Hence, a) Dimensions of miniature is 0.17 × 0.08 × 0.5, b) 0.006 ft³.

6 0

3 years ago

If 2tanA=3tanB,then prove that tan(A-B)=sin2B/(5-cos2B) ...?

andreev551 [17]

Tan ( A - B ) = ( tan A - tan B ) / ( 1 + tan A tan B )
tan A = 3 tan B/2
tan ( A - B ) = ((3 tan B/ 2)-tan B) / ( 1 + 3 tan² B/2)=
= (tan B/2) / ( 2 + 3 sin²B/cos²B )=
= (sin B / cos B) / (( 2cos² B+3sin²B)/cos²B)=
=( sin B cos B ) / ( 2 cos²B + 3 ( 1 - cos² B ) ) =
= (sin B cos B ) / ( 2 cos² B + 3 - 3 cos² B ) =
= ( sin 2 B ) / 2 ( 3 - cos² B ) =
= ( sin 2 B ) / ( 6 - cos² B )=
= ( sin 2 B ) / ( 5 + 1 - 2 cos² B )=
= ( sin 2 B ) / ( 5 + sin² B + cos ² B - 2 cos² B ) =
= ( sin 2 B ) / ( 5 - ( cos² B - sin² B ) ) =
= ( sin 2 B ) / ( 5 - cos 2 B ) - correct

8 0

3 years ago