Polymer composite materials have gained popularity because they have high strength to weight ratios and are relatively easy and inexpensive to manufacture. However, their nondegradable nature has prompted development of environmentally friendly composites using natural materials. The article "Properties of Waste Silk Shod Fiber/Cellulose Green Composite Films" (. of Composite Materials, 2012: 123-127) reported that for a sample of 10 specimens with 2% fiber content, the sample mean tensile strength (MPa) was 51.3 and the sample standard deviation was 1.2. Suppose the true average strength for 0% fibers (pure cellulose) is known to be 48 MPa. Does the data provide compelling evidence for concluding that true average strength for the WSF/cellulose composite exceeds this value?

Answer:

U = 67.6 degrees

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

cos U = adj side / hypotenuse

cos U = sqrt(10)/ sqrt(69)

cos U = sqrt(10/69)

Taking the inverse cos of each side

cos ^-1( cos U) =  cos ^-1(sqrt(10/69))

U = 67.62335

To the nearest tenth

U = 67.6 degrees

Step-by-step explanation:

here's the answer to your question

Answer:

C. 76 + 7i

Step-by-step explanation:

49 squared is 7 and since it's negative, it is an imaginary number. Therefore, it is 7i. Which leaves C to be the correct option.

Similar triangles are proportional, meaning one will be a factor larger or smaller than the other. This factor will be the same for all of the sides. So, we can say that one corresponding pair of sides is equal to another corresponding pair of sides.

BA / ED = AC / CD

42 / 6 = (64 - x) / (x)

6(64 - x) = 42(x)

384 - 6x = 42x

384 = 48x

x = 8

Hope this helps!

Answer:

The measure of ∠1 and ∠2 is 105° and 75° respectively

Step-by-step explanation:

In the given figure, line a is parallel to line b.

We need to find the measure of angles 1 and 2.

∠2 = 75° (because they form corresponding angles)

We know that, interior angles add up to 180. So,

∠1 +75 = 180

∠1 = 180-75

∠1 = 105°

So, the measure of ∠1 and ∠2 is 105° and 75° respectively.

Answer:

C.I = (0.259,1.175) -> Fail to Reject H0  

Step-by-step explanation:

Answer:

50

Step-by-step explanation:

So we know that 42/3=14.

3 years before was:

14-3=11

42-3=39

The sum of 11+39 is 50

Answer:

95

Step-by-step explanation:

300-20=280

280+100=380

380÷4=95

There you go...

Answer:

u^2- 18u +81 = (u-9)^2

Step-by-step explanation:

u^2- 18u +

Take the u coefficient

-18

Divide by 2

-18/2 = -9

Square it

(-9)^2 = 81

u^2- 18u +81 = (u-9)^2

Answer:

The blank should contain 81

Step-by-step explanation:

E = u^2 - 18u + (-18/2)^2

E = (u^2 - 18u + 9^2)

E = (u - 9)^2

To be perfectly correct what you have there is a perfect square, but you need to subtract out (9/2)^2 to make it a valid statement.

E = (u - 9)^2 - 81

hope it helps

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9514 1404 393

Answer:

  see attached

Step-by-step explanation:

Take note of the inequality symbol. It is < (not ≤), so the "equal to" case is not included. That means the line 3x+4y=-16 is not part of the solution set. That boundary line is graphed as a dashed line.

Take note of where the variables are in relation to the inequality symbol. Both are on the "less than" side, so the shading of the graph will be where the values of x and y are less than those on the boundary line. The boundary line has a negative slope, so the values less than those on the boundary are to the left and below the line.

Plot the dashed boundary line 3x +4y = -16, or y = -3/4x -4, and shade the area below and to its left.

9514 1404 393

Answer:

  (c)  f(x) is an even degree polynomial with a positive leading coefficient.

Step-by-step explanation:

The leading terms of the two functions are ...

  f(x): x² (even degree, positive coefficient: 1)

  g(x): x³ (odd degree, positive coefficient: 1)

Then it is true that ...

  f(x) is an even degree polynomial with a positive leading coefficient

Let breadth be x

We know

[tex]\boxed{\sf Area_{(Rectangle)}=Length\times Breadth}[/tex]

[tex]\\ \sf\longmapsto x(x+4)=22[/tex]

[tex]\\ \sf\longmapsto x^2+4x=22[/tex]

[tex]\\ \sf\longmapsto x^2+4x-22=0[/tex]

[tex]\\ \sf\longmapsto x=-2\pm\sqrt{26}[/tex]

It doesnot have any real roots

Answer:

6

Step-by-step explanation:

Given :

Sample size, n = 36

Sample variance, s² = 1296

The estimated standard error can be obtained using the relation :

Standard Error, S. E = standard deviation / √n

Standard deviation, s = √1296 = 36

S.E = 36/√36

S.E = 36/6

S.E = 6

Hence, estimated standard error = 6

Answer:

I'd be estimatining the answer between 29-31.

Draw a line of best fit. It will be easier to make the estimation.

Answer:

C

Step-by-step explanation:

the fibrin definition tells us that the first term of the sequence a1 = 6

so, B is out.

and for every following term we always add 7 to every previous term to create the next one.

so, when I add 7 to 6, what is my second term in the sequence ? 7+6 = 13

not 42, not -7

therefore, only C is correct.

and 13+7 = 20

and 20+7 = 27

it all fits

9514 1404 393

Answer:

  (a) (-∞, -8), (-5, -2), (2, 5)

  (b) -8, -2, 5

  (c) negative

  (d) 6

Step-by-step explanation:

(a) The function is increasing on intervals where the graph slopes upward left-to-right. Those are (-∞, -8), (-5, -2), and (2, 5).

__

(b) The local maxima are at the right end of each interval on which the function is increasing: -8, -2, 5.

__

(c) The function opens downward (∩), so has a negative leading coefficient.

__

(d) There are three local maxima and two local minima (left end of an increasing interval), so a total o 5 turning points. The degree of the polynomial is at least one more than this: 6.

Answer:

A. If the side lengths are the same, then a triangle is not scalene.

Step-by-step explanation:

A triangle can be defined as a two-dimensional shape that comprises three (3) sides, three (3) vertices and three (3) angles.

Simply stated, any polygon with three (3) lengths of sides is a triangle.

In Geometry, a triangle is considered to be the most important shape.

Generally, there are three (3) main types of triangle based on the length of their sides and these include;

I. Equilateral triangle: it has all of its three (3) sides and interior angles equal.

II. Isosceles triangle: it has two (2) of its sides equal in length and two (2) equal angles.

III. Scalene triangle: it has all of its three (3) sides and interior angles different in length and size respectively.

Answer:

H0: µd = 0 (claim)

H1: µd ≠ 0

This is a two-tail t-test for µd

Step-by-step explanation:

This is a paired (dependent) sample test, with its hypothesis is written as :

H0: µd = 0

H1: µd ≠ 0

From the equality sign used in the hypothesis declaration, a not equal to ≠ sign in the alternative hypothesis is used for a two tailed t test

The data isn't attached, however bce the test statistic cannot be obtained. However, the test statistic formular for a paired sample is given as :

T = dbar / (Sd/√n)

dbar = mean of the difference ; Sd = standard deviation of the difference.

Answer:

The answer is 1

.............

please mark this answer as brainlist

Answer:

68.3 degrees

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

tan I = opp side / adj side

tan I = sqrt(82) / sqrt(13)

tan I = sqrt(82/13)

Taking the inverse tan of each side

tan ^-1 ( tan I) = tan ^-1( sqrt(82/13))

I = 68.2892

Rounding to the nearest tenth

I = 68.3 degrees

Answer:

D.

Step-by-step explanation:

.

The number of planes that can be drawn that pass through point A is 1.

A perpendicular line creates an angle of 90° with a line or a plane. If a line exists to be drawn from a point to a line or a plane it can only be one. In this case, a line exists to be drawn through a point A to a plane P. If the line stands to be perpendicular, then it exists only one.

Therefore, the correct answer is option D. 1.

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Answer:

Step-by-step explanation:

a) Probability-Above 30 min = 5.72% = .0572

b) Probability-Above 15 min =  99.11% = .9911

c) *Probability-Between  1 - 59.49% = .4051

d) 19.136 minutes  z = -1.28

a) The probability that trip will take at least 1/2 hour will be 0.0606.

b) The percentage of time the lawyer is late for work will be 99.18%.

c) The probability that lawyer misses coffee will be 0.3659.

d) The length of time above which we find the slowest 10​% of trips will be 0.5438.

e) The probability that exactly 2 out of 3 trips will take at least one half

1/2 hour is 0.0103.

What do you mean by normal distribution ?

A probability distribution known as a "normal distribution" shows that data are more likely to occur when they are close to the mean than when they are far from the mean.

Let assume the time taken for a one way trip be x .

x ⇒ N( μ , σ ²)

x  ⇒ N( 24 , 3.8 ²)

a)

The probability that trip will take at least 1/2 hour or 30 minutes will be :

P ( x ≥ 30)

= P [ (x - μ) / σ ≥ (30 - μ) / σ ]

We know that , (x - μ) / σ = z.

= P [ z ≥ (30 - 24) / 3.8)]

= P [ z ≥ 1.578 ]

= 1 - P [  z ≤ 1.578 ]

Now , using the standard normal table :

P ( x ≥ 30)

= 1 - 0.9394

= 0.0606

b)

The percentage of the time the lawyer is late for work will be :

P ( x  ≥ 15)

= P [ z ≥ -2.368 ]

= P [  z ≤ 2.368]

= 0.9918

or

99.18%

c)

The probability that lawyer misses coffee :

P ( 15 < x < 25 ) = P ( x < 25 ) - P ( x < 15)

= P [  z < 0.263] - P ( z < -2.368)

or

= 0.3659

d)

The length of time above which we find the slowest 10​% of trips :

P( x ≥ X ) ≤ 0.10

=  0.5438

e)

Let's assume that y represents the number of trips that takes at least half hour.

y ⇒ B ( n , p)

y ⇒ B ( 3 , 0.0606)

So , the probability that exactly 2 out of 3 trips will take at least one half

1/2 hour is :

P ( Y = 2 )

= 3C2 × (0.0606)² × ( 1 - 0.0606)

= 0.0103

Therefore , the answers are :

a) The probability that trip will take at least 1/2 hour will be 0.0606.

b) The percentage of time the lawyer is late for work will be 99.18%.

c) The probability that lawyer misses coffee will be 0.3659.

d) The length of time above which we find the slowest 10​% of trips will be 0.5438.

e) The probability that exactly 2 out of 3 trips will take at least one half

1/2 hour is 0.0103.

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Answer:

x = 14

JHK =  21

Step-by-step explanation:

The angles are vertical angles and vertical angles are equal

3x-21 = x+7

Subtract x from each side

3x-x -21 = x+7-x

2x-21 = 7

Add 21 to each side

2x-21+21 = 7+21

2x = 28

Divide by 2

2x/2 =28/2

x = 14

JHK = 3x-21 = 3(14) -21 = 42-21 = 21

Answer:

Because ∠GHI and ∠JHK are vertical angles, they're congruent. Therefore, set their angle measures equal to each other & solve for x.

[tex]x+7=3x-21\\x-3x=-7-21\\-2x=-28\\x=\frac{-28}{-2} =14\°[/tex]

Substitute in the value of x to find ∠JHK:

[tex]3x-21=3(14)-21=42-21=21\°[/tex]

Answer:

a) 75

b) 4.33

c) 0.75

d) [tex]3.2 \times 10^{-13}[/tex] probability that no one in a simple random sample of 100 young adults owns a landline

e) [tex]6.2 \times 10^{-61}[/tex] probability that everyone in a simple random sample of 100 young adults owns a landline.

f) Binomial, with [tex]n = 100, p = 0.75[/tex]

g) [tex]4.5 \times 10^{-8}[/tex] probability that exactly half the young adults in a simple random sample of 100 do not own a landline.

Step-by-step explanation:

For each young adult, there are only two possible outcomes. Either they do not own a landline, or they do. The probability of an young adult not having a landline is independent of any other adult, which means that the binomial probability distribution is used to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.

[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]

And p is the probability of X happening.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

75% of all young adults between the ages of 18-35 do not have a landline in their homes and only use a cell phone at home.

This means that [tex]p = 0.75[/tex]

(a) On average, how many young adults do not own a landline in a random sample of 100?

Sample of 100, so [tex]n = 100[/tex]

[tex]E(X) = np = 100(0.75) = 75[/tex]

(b) What is the standard deviation of probability of young adults who do not own a landline in a simple random sample of 100?

[tex]\sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{100(0.75)(0.25)} = 4.33[/tex]

(c) What is the proportion of young adults who do not own a landline?

The estimation, of 75% = 0.75.

(d) What is the probability that no one in a simple random sample of 100 young adults owns a landline?

This is P(X = 100), that is, all do not own. So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 100) = C_{100,100}.(0.75)^{100}.(0.25)^{0} = 3.2 \times 10^{-13}[/tex]

[tex]3.2 \times 10^{-13}[/tex] probability that no one in a simple random sample of 100 young adults owns a landline.

(e) What is the probability that everyone in a simple random sample of 100 young adults owns a landline?

This is P(X = 0), that is, all own. So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 0) = C_{100,0}.(0.75)^{0}.(0.25)^{100} = 6.2 \times 10^{-61}[/tex]

[tex]6.2 \times 10^{-61}[/tex] probability that everyone in a simple random sample of 100 young adults owns a landline.

(f) What is the distribution of the number of young adults in a sample of 100 who do not own a landline?

Binomial, with [tex]n = 100, p = 0.75[/tex]

(g) What is the probability that exactly half the young adults in a simple random sample of 100 do not own a landline?

This is P(X = 50). So

[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]

[tex]P(X = 50) = C_{100,50}.(0.75)^{50}.(0.25)^{50} = 4.5 \times 10^{-8}[/tex]

[tex]4.5 \times 10^{-8}[/tex] probability that exactly half the young adults in a simple random sample of 100 do not own a landline.

Answer:

15 cups

Step-by-step explanation:

1 quart = 4 cups

3.75 quarts = (3.75 * 4) cups

3.75 quarts = 15 cups

3.75 quarts mean 15 cups

The unitary approach is a strategy for problem-solving that involves first determining the value of a single unit, then multiplying that value to determine the required value.

Given

1 quart = 4 cups

3.75 quarts = (3.75 * 4) cups

3.75 quarts = 15 cups

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Answer:

1375

Step-by-step explanation:

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:

[tex]C=1.15cents[/tex]

Step-by-step explanation:

Generally the equation for is mathematically given by

Charge Power P=4watts

Rate r=12cents/hour

Time consumed T=24

Generally

Power consumed by smartphone in 24 hours

[tex]P_t=P*T\\\\P_t=24*4[/tex]

[tex]P_t=0.096kwh[/tex]

Therefore the Cost will be

[tex]C=12*0.096kwh[/tex]

[tex]C=1.15cents[/tex]

Answer: 50.2 is it  

Step-by-step explanation: thats easy

Probability helps us to know the chances of an event occurring. The probability of selecting a heart and then selecting a diamond is 144/2652.

Probability helps us to know the chances of an event occurring.

[tex]\rm Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}[/tex]

Given that Two cards are selected with replacement from a standard deck of 52 cards. Therefore, the probability of selecting a heart and then selecting a diamond is,

Probability = (12/52) × (12/51)

Probability = 144/2652

Hence, The probability of selecting a heart and then selecting a diamond is 144/2652.

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Answer:

C

Step-by-step explanation: