A person on the top of a tall building looks through his binoculars at his friend that is 300 ft away from the building on the ground. If the angle of depression from the person on the building is 30°, how tall is the building?

The standard deviation for the given data items is 2.6

The standard deviation of the given data items can be calculated by taking the square root of the variance.

Variance is a measure of variability and it is calculated by taking the average of squared deviations from the mean.

Hence, we will first determine the mean of the given data items.

Mean is simply the average of the numbers.

Therefore mean of the given data items is

[tex]Mean = \frac{9+11+11+16}{4}[/tex]

[tex]Mean = \frac{47}{4}[/tex]

Mean = 11.75

Now, for the variance of the data

[tex]Variance = \frac{(9-11.75)^{2}+(11-11.75)^{2}+(11-11.75)^{2}+(16-11.75)^{2} }{4}[/tex]

[tex]Variance = \frac{(-2.75)^{2}+(-0.75)^{2}+(-0.75)^{2}+(4.25)^{2} }{4}[/tex]

[tex]Variance = \frac{7.5625+0.5625+0.5625+18.0625}{4}[/tex]

[tex]Variance = \frac{26.75}{4}\\[/tex]

∴ Variance = 6.6875

But,

Standard deviation [tex]= \sqrt{Varinace}[/tex]

∴Standard deviation  [tex]=\sqrt{6.6875}[/tex]

Standard deviation = 2.586

Standard deviation ≅ 2.6

Hence, the standard deviation for the given data items is 2.6

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Solution :

It is given that the device works satisfactorily if it makes an average of no more than [tex]0.2[/tex] errors per hour.

The number of errors thus follows the Poisson distribution.

It is given that in [tex]5[/tex] hours test period, the number of the errors follows is

= [tex]0.2 \times 5[/tex]

= 1 error

Let X = the number of the errors in the [tex]5[/tex] hours

[tex]$X \sim \text{Poisson } (\lambda = 0.2 \times 5 =1)$[/tex]

Now that we want to find the [tex]\text{probability}[/tex] that a [tex]\text{satisfactory device}[/tex] will be misdiagnosed as "[tex]\text{unsatisfactory}[/tex]" on the basis of this test. We know that device will be unsatisfactory if it makes more than [tex]1[/tex] error in the test. So we will determine probability that X is greater than [tex]1[/tex] to get required answer.

So the required probability is :

[tex]P(X>1)[/tex]

[tex]$=1-P(X \leq 1)$[/tex]

[tex]$=1-[P(X=0)+P(X=1)]$[/tex]

[tex]$=1- \left( \frac{e^{-1} 1^0}{0!} + \frac{e^{-1} 1^0}{1!} \right) $[/tex]

[tex]$=1-(2 \times e^{-1})$[/tex]

[tex]$=1-( 2 \times 0.367879)$[/tex]

[tex]$=1-0.735759$[/tex]

[tex]=0.264241[/tex]

So the [tex]\text{probability}[/tex] that the [tex]\text{satisfactory device}[/tex] will be misdiagnosed as "[tex]\text{unsatisfactory}[/tex]" on the basis of the test whose result is 0.264241

Answer:

Binomial probability refers to the probability of exactly x successes on n repeated trials in an experiment which has two possible outcomes (commonly called a binomial experiment).

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Explanation:

You can use the AAS (angle angle side) theorem to prove that triangle ABD is congruent to triangle CBD.

From there, we can then say that AD and DC are the same length

AD = DC

3y+6 = 5y-18

3y-5y = -18-6

-2y = -24

y = (-24)/(-2)

y = 12

The range is virtually the answer to the question,

"In which interval can find all y-values of the function".

So you look at the y-axis and see that your function begins with [tex]y=-5[/tex] (including -5 because of the dot on the graph) and ends at including [tex]y=-1[/tex].

So the interval notation is,

[tex]y\in[-5,-1][/tex]

But you are asked to specify the set notation of the interval, to do so first rewrite the interval using inequality operators, say we find some y in between (and including) -5 and -1,

[tex]-5\leq y\leq-1[/tex]

To specify that this is a set use curly bracelets and a bar,

[tex]\{y\mid-5\leq y\leq-1\}[/tex].

The y before bar is a step function and everything followed after the vertical bar is the range of the step function.

Hope this helps.

Using it's concept, it is found that the range of f(x) is given by:

{y|-5 <= -y <= -1}

The range of a function is the set that contains all possible output values. In a graph, it is given by the values of y, that is, the values of the vertical axis.

In the function described by this graph, the vertical axis assumes values between -1 and -5, inclusive, hence the range is given by:

{y|-5 <= -y <= -1}

More can be learned about the range of a function at https://brainly.com/question/24374080

Answer:

E. 0.17

Step-by-step explanation:

Mean:

Sum of all values divided by the number of values, so:

[tex]\overline{x} = \frac{5.1 + 5 + 4.9 + 5.4 + 5.2}{5} = 5.12[/tex]

Standard deviation:

Square root of the sum of the difference squared between each value and the mean, divided by the sample size, so:

[tex]s = \sqrt{\frac{(5.1-5.12)^2 + (5-5.12)^2 + (4.9-5.12)^2 + (5.4-5.12)^2 + (5.2-5.12)^2}{5}} = 0.172[/tex]

Thus the correct answer is given by option E.

Answer:

just show the questions i will help

Step-by-step explanation:

Answer: a

Step-by-step explanation:

Janelle can conclude that the medication used in this experiment was effective and it decreases sneezing.

A control experiment can be defined as a type of experiment in which a condition assumed to be a probable cause of an effect is compared with the same situation without involving or using the suspected condition.

A treatment group refers to a group of participants in an experiment that are exposed to some manipulation in the independent variable such as an administration of medication to a particular group.

Thus, Janelle can conclude that the medication used in this experiment was effective and it decreases sneezing because the treatment group show reduced signs of sneezing.

Read more on an experiment here: https://brainly.com/question/17542127

Answer:

37°

Step-by-step explanation:

that is the procedure above

Answer:

0.2587 = 25.87% probability you will roll a purple on your next toss of the die.

Step-by-step explanation:

A probability is the number of desired outcomes divided by the number of total outcomes.

In an experimental probability, which is the case in this question, the number of outcomes is taken from previous experiments.

In this question:

44 + 37 + 41 + 21 = 143 tosses.

37 purple.

What is the probability you will roll a purple on your next toss of the die?

[tex]p = \frac{37}{143} = 0.2587[/tex]

0.2587 = 25.87% probability you will roll a purple on your next toss of the die.

A factor is a natural number that can be multiplied by another natural number to get a value. The greatest common factor refers to when one compares the factors of two numbers, the largest natural number that both numbers have in common is the number's greatest common factor.

In the case of ([tex]m^2[/tex]) and ([tex]m^4[/tex]), the greatest common factor is ([tex]m^2[/tex]) because there are no factors of ([tex]m^2[/tex]) that are larger than it. No number can have a factor larger than itself. Since ([tex]m^2[/tex]) is also a factor of ([tex]m^4[/tex]) it is the greatest common factor of the two numbers.

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Answer:

  -1/2

Step-by-step explanation:

The factor outside parentheses multiplies each term inside.

  5/2(-8/5 +7/5)

  = (5/2)(-8/5) +(5/2)(7/5)

  = -8/2 +7/2 = -1/2

Step-by-step explanation:

question 1

angle DBA=90°, meaning to find m<D you have to add 90+38 then subtract by 180, because ABD is a triangle

90+18+m<D=180

108+m<D=180

m<D=180-108

=72°

question 2

m<D again in this case angle ABD is also 90

m<D=180-(90+48)

=180-138

=42°

I hope this helps

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Answer:

  geometric sequence

Step-by-step explanation:

The terms of the sequence have a common ratio of -12/3 = -4, so the sequence is geometric. The general term is ...

  an = 3(-4)^(n-1)

so the sum can be written as ...

  [tex]\displaystyle\sum_{n=0}^\infty3(-4)^n[/tex]

(Note the summation starts at n=0, corresponding to a first term of 3.)

Answer:

6x10^4

Step-by-step explanation:

Answer:

sauce is 177013

Step-by-step explanation:

Answer:

"D"

if you multiply by Conjugate

the denominator would end up A^2 - b^2

the answer has 25 - 10x

that is D

Step-by-step explanation:

Answer:

5 * 10 * 10 * 9 = 4500

Step-by-step explanation:

The given graph is a line and he line is the distance between two points.  The required equation of the line is y = 0.5x + 5

The given graph is a line and he line is the distance between two points. The equation of a line is represented as;

y = mx+ b

Given the coordinate points (-5, 4) and (1, 7)

Get the slope

Slope = 7-4/1-(-5)

Slope = 3/6

Slope = 0.5

The intercept is 5 (the point where the line cuts the y-axis)

Determine the required equation

y = 0.5x + 5

Hence the required equation of the line is y = 0.5x + 5

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Answer:

A

Step-by-step explanation:

I guess that is it may be

Based on the information, the triangles share two sides but have one different side. one included angle is bigger than the other.

This means that the triangle with side 2x-4 must be smaller than the triangle with the side 10.

Let first, find it minimum amount. A triangle side must be greater than zero so

[tex]2x - 4 > 0[/tex]

[tex]2x > 4[/tex]

[tex]x > 2[/tex]

The triangle side must be smaller than 10.

[tex]2x - 4 < 10[/tex]

[tex]2x < 14[/tex]

[tex]x < 7[/tex]

So x must be greater than 2 but must be smaller than 7.

Answer:

24 boxes, 1 chocolate remaining

Step-by-step explanation:

289 chocolates total, each box is 12.

just divide it and whatever is left will be your remainder.

289/12 = 24 boxes, 1 chocolate remaining

sub to gauthmath sub reddit for more help like this !

Answer:

9/25

Step-by-step explanation:

3 novels , 1 bio , 1 poetry = 5 books

P( novel) = novels / books

               = 3/5

Book is returned

3 novels , 1 bio , 1 poetry = 5 books

P( novel) = novels / books

               = 3/5

P(novel, return, novel) = 3/5 * 3/5 = 9/25

Given:

E is the midpoint of AD and BC.

To prove:

[tex]\Delta AEC\cong DEB[/tex]

Proof:

Statement                                                    Reason

1. E is the midpoint of AD and BC            1. Given

2. [tex]AE\cong DE[/tex]                                              2. Definition of midpoint

3. [tex]CE\cong BE[/tex]                                              3. Definition of midpoint

4. [tex]\angle AEC\cong \angle DEB[/tex]                                    4. Vertically opposite angle

5. [tex]\triangle AEC\cong \triangle DEB[/tex]                                   5. SAS congruence postulate

Hence proved.

Complete Question

A manufacturer of nickel-hydrogen batteries randomly selects 100 nickel plates for test cells, cycles them a specified number of times, and determines that 11 of the plates have blistered. Does this provide compelling evidence for concluding that more than 10% of plates blister under such circumstances?

A) State H_0 and H_a, (5 pts)

B) Test the hypothesis using the P-Value approach at a significance level of 4%: (15 pts)

Expert Answer

Answer:

a)[tex]H_0:p=0.10[/tex]

  [tex]H_a:p>0.10[/tex]

b) We fail to reject Null hypothesis

Step-by-step explanation:

From the question we are told that:

Sample size n=100

No. with blistered x=11

a)

Generally the Hypothesis given as

[tex]H_0:p=0.10[/tex]

[tex]H_a:p>0.10[/tex]

b)

Since p=0.10

Therefore

[tex]p'=\frac{11}{100}[/tex]

[tex]p'=0.11[/tex]

Test statistics

[tex]Z=\frac{p'-p}{\sqrt{p(1-p)}}[/tex]

[tex]Z=\frac{0.11-0.10}{\sqrt{0.10*0.90/100}}[/tex]

[tex]Z=1.33[/tex]

From table

[tex]P-Value =0.092[/tex]

Therefore

P-value >0.04 significance level

Hence,We cannot conclude that at [tex]4\%[/tex] significance level the proportion is greater than [tex]10\%[/tex]

We fail to reject Null hypothesis

Answer:

a = 4[tex]\sqrt{3}[/tex]

Step-by-step explanation:

Using the cosine ratio in the right triangle and the exact value

cos60° = [tex]\frac{1}{2}[/tex] , then

cos60° = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{2\sqrt{3} }{a}[/tex] = [tex]\frac{1}{2}[/tex] ( cross- multiply )

a = 4[tex]\sqrt{3}[/tex]

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Answer:

Step-by-step explanation:

The highest degree term is -2v^3. Its degree is 3, so the degree of the polynomial is 3. Its coefficient is -2, so the leading coefficient is -2.

Answer:

On the way out the train traveled at about 40 mph, while on the return it did so at 20 mph.

Step-by-step explanation:

Since an empty freight train traveled 60 miles from an auto assembly plant to an oil refinery, and there, its tank cars were filled with petroleum products, and it returned on the same route to the plant, and the total travel time for the train was 4.5 hours, if the train traveled 20 mph slower with the tank cars full, to determine how fast did the train travel in each direction the following calculation must be performed:

60/20 = 3

60/40 = 1.5

60/20 = 3

3 + 1.5 = 4.5

Therefore, on the way out the train traveled at about 40 mph, while on the return it did so at 20 mph.