7 2/5= 2/3x -4 1/2 plz helpp

Complete Question

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. An article reported that for a sample of 10 specimens with 2% fiber content, the sample mean tensile strength (MPa) was 51.1 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? (Use α = 0.05.)  

t=8.169  

P-value= ?

Answer:

a)  [tex]P-value=0[/tex]

b)  Hence,We FAil to reject the alternative hypothesis and accept that the true average strength for the WSF/  cellulose composite exceeds 48 MPa.

Step-by-step explanation:

From the question we are told that:

Sample size [tex]n=10[/tex]

Mean [tex]\=x= 51.3[/tex]

Standard deviation [tex]\sigma=1.2[/tex]

Significance level is taken as [tex]\alpha=0.05[/tex]

t test statistics

[tex]t=8.169[/tex]

Therefore

[tex]P-Value=P(t>8.169)[/tex]

Critical point

[tex]t_{\alpha,df}[/tex]

[tex]\alpha=0.05[/tex]

[tex]df=10-1=>9[/tex]

Therefore

P-value from T distribution table

[tex]P-value=0[/tex]

Conclusion

[tex]P-value (0)< \alpha(0.05)[/tex]

We Reject the Null Hypothesis [tex]H_0[/tex]

Hence,We FAil to reject the alternative hypothesis and accept that the true average strength for the WSF/  cellulose composite exceeds 48 MPa.

Answer:

you never showed the chocies

Step-by-step explanation:

Step-by-step explanation:

Lets break this word problem down:

"The difference" means we're going to be finding x - y ("difference" means we're finding how much one value "differs" from the other)

"a number and it's opposite" so we're doing x - y, where y = -x. So already, we can re-write this as x - (-x) or x + x

"is 28" so x + x = 28 ("is" always means "equals")

"Find the number" so we're finding x.

x - (-x) = 28  (I went back a step so I could write everything out more plainly)

simplify

x + x = 28

add

2x = 28

divide both sides by 2 to get x on its own

x = 14

Answer:

14

Answer:

6squareroot2

Step-by-step explanation:

that's the answer I think

Answer:

-3/8 is located on the right of -1

Step-by-step explanation:

-3/8 is left of -1 because -3/8 is larger than -1.

Answer:

-200

Step-by-step explanation:

ATQ, a+11d=-13 and a+a+d+a+2d+a+3d=24, 4a+6d=24. Solving this, we get a=9 and d=-2. Sum of the first 20 terms is 10*(18+(19)*(-2))=-200

Answer:

$64.15

Step-by-step explanation:

to solve this problem, first we should figure out how much money that the cashier gave them back, and then subtract that from $80 (which was what Matt and his siblings gave the cashier) to find out how much the perfume cost.

it is given that:

they gave the cashier $80.

the cashier gave them back 1 ten-dollar bill ($10), 1 five-dollar bill ($5), 8 dimes ($0.80 or 80 cents) , and 1 nickel ($0.05 or 5 cents)

$10+$5+$0.80+$0.05=$15.85

the total amount of money that the cashier gave them back is $15.85

to find how much the perfume cost:

$80-$15.85=$64.15

so, the perfume cost $64.15

As both angles are supplementary

[tex]\\ \Large\sf\longmapsto 3x+(2x+3y)=180°[/tex]

[tex]\\ \Large\sf\longmapsto 3x+2x+3y=180[/tex]

[tex]\\ \Large\sf\longmapsto 5x+3y=180[/tex]

[tex]\\ \Large\sf\longmapsto 3y=180-5x[/tex]

[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5x}{3}[/tex]

And

[tex]\\ \Large\sf\longmapsto 3x=90[/tex]

[tex]\\ \Large\sf\longmapsto x=\dfrac{90}{3}[/tex]

[tex]\\ \Large\sf\longmapsto x=30[/tex]

Now

[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5x}{3}[/tex]

[tex]\\ \Large\sf\longmapsto y=\dfrac{180-5(30)}{3}[/tex]

[tex]\\ \Large\sf\longmapsto y=\dfrac{180-150}{3}[/tex]

[tex]\\ \Large\sf\longmapsto y=\dfrac{30}{3}[/tex]

[tex]\\ \Large\sf\longmapsto y=10[/tex]

Answer: 24 feet

Step-by-step explanation: i just guessed it on pluto and got it right. please leave a like if it worked

The length of another axis for the given ellipse will be around 25.6125 feet so none of the options will be correct.

a regular oval form produced when a cone is cut by an oblique plane that does not intersect the base, or when a point moves in a plane so that the sum of its distances from two other points remains constant.

In another word, an ellipse is a curve that becomes by a point moving in such a way that the sum of its distances from two fixed points is a closed planar curve produced.

General equation of an ellipse

(x 2 / a 2 )+ (y2 / b 2 )= 1

Given that

the plot of land is 40 feet across one axis

so  2a = 40 feet

a = 20 feet

The foci are 16 feet from the center so

c = 16

Now we know that

c = √(b² - a²)  

c² = b² - a²

16² = b² - 20²

b = 25.6125  

So, the length of the minor axis will be around 25.6125 feet.

To learn more about ellipse,

https://brainly.com/question/14281133

#SPJ2

Volume = πr²h

Radius = 3yd

Height = 12yd

Take π = 22/7

Volume = 22/7×3×3×12

= 2376/7

= 339.4285714yd³

Rounding off to nearest tenth

= 339.43yd³

Answered by Gauthmath must click thanks and mark brainliest

Answer:

The sign would remain the same.

It would have the same value.

ED2021

Answer: b&c

The sign would remain the same.

It would have the same value.

Given:

A credit card advertises an annual interest rate of 23%.

To find:

The equivalent monthly interest rate.

Solution:

We know that,

1 year = 12 months

It is given that, the credit card advertises an annual interest rate of 23%. So, the equivalent monthly interest rate is:

[tex]\dfrac{23\%}{12}=1\dfrac{11}{12}\%[/tex]

[tex]\dfrac{23\%}{12}\approx 1.9167\%[/tex]

Therefore, the equivalent monthly interest rate is [tex]1\dfrac{11}{12}\%[/tex] and the approximate equivalent monthly interest rate is 1.9167%.

The volume of air inside the cube is 1887.4 cubic inches. Then the correct option is C.

It deals with the size of geometry, region, and density of the different forms both 2D and 3D.

A ball inside of a cube has a volume of 113 cubic inches. If each side of the cube measures 12.6 inches.

Then the volume of air inside the cube will be given as the difference between the volume of the cube and the sphere.

Air volume = Volume of the cube - Volume of the sphere

Air volume = 12.6³ - 113

Air volume = 2000.376 - 113

Air volume = 1887.376

Air volume ≅ 1,887.4

More about the geometry link is given below.

https://brainly.com/question/7558603

#SPJ2

Answer:

1887.4 cubic inches

Step-by-step explanation:

Answer:

[tex]x= 80^o[/tex]

Step-by-step explanation:

Given

[tex]\angle Z = 36^o[/tex]

[tex]\angle WYZ = 100^o[/tex]

Required

Find x

[tex]\angle WYZ[/tex] and x are on a straight line.

So:

[tex]\angle WYZ + x= 180^o[/tex]

Make x the subject

[tex]x= 180^o -\angle WYZ[/tex]

Substitute known value

[tex]x= 180^o -100^o[/tex]

[tex]x= 80^o[/tex]

Answer:

80 is correct

Step-by-step explanation:

Answer:

Approximately 68% of people have IQs between 84 and 116.

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

Approximately 68% of the measures are within 1 standard deviation of the mean.

Approximately 95% of the measures are within 2 standard deviations of the mean.

Approximately 99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean of 100, standard deviation of 16.

Percentage of people with IQs between 84 and 116.

84 = 100 - 16

116 = 100 + 16

So within 1 standard deviation of the mean, which, by the Empirical Rule, is approximately 68%.

Answer:

16 cm^2/min

Step-by-step explanation:

dV/dt=24

V=a^3, differentiate with respect to t

dV/dt=3a^2*da/dt, a^2*da/dt=8

S=6a^2, 216=6a^2. a=6. da/dt=(8/36)

dS/dt=12*a*da/dt=12*(8/6)=16 cm^2/min

Answer:

(0,-1)

Step-by-step explanation:

(6-6,0-1)

or, (0,-1)

Answer:

Step-by-step explanation:

First number is 1/10

Last letter is 1/26

The second digit is 1/9

The first letter is 1/25

1/10 * 1/26 * 1/9 * 1/25

0.00001709

This assumes no duplication is allowed,

If there are duplications

then 1/10 * 1/10 * 1/26 * 1/26

0.000014782

Answer:

Step-by-step explan

Answer:

Casey's monthly charge for making 1,100 minutes of calls is $70.

Step-by-step explanation:

We can write a piecewise function to model the situation.

Since Casey's phone service only charges a monthly fee of $30 for the first 1000 minutes, we can write that for calling t minutes:

[tex]\displaystyle C(t) = 30\text{ if } t\leq 1000[/tex]

In other words, the total cost is only $30 is the total minutes of call is less than  1000 minutes.

However, if the total minutes of calls is greater than 1000, then its $0.40 per minute on top of the 30. Thus:

[tex]\displaystyle C(t) = 30 + 0.4(t-1000)\text{ if } t>1000[/tex]

All together, our piecewise function will be:

[tex]\displaystyle C(t) = \begin{cases} 30 & t\leq 1000 \\ 30 + 0.4(t-1000) & t>1000\end{cases}[/tex]

We want to determine Caseys monthly charge if he makes 1,100 minutes of calls. So, t = 1100. Since 1100 > 1000, we will use the second equation. This yields:

[tex]C(1100)= 30+0.4((1100)-1000)[/tex]

Evaluate:

[tex]\displaystyle C(1100) = 30+0.4(100) = 30+40=\$70[/tex]

Casey's monthly charge for using 1,100 minutes of call is $70.

Answer:

See attachment for graph

Step-by-step explanation:

Given

[tex]f(x) = \left[\begin{array}{cc}-1&x<-1\\0&-1\le x \le -1\\1&x>1\end{array}\right[/tex]

Required

The graph of the step function

Before plotting the graph, it should be noted that:

[tex]\le[/tex] and [tex]\ge[/tex] use closed circle at its end

[tex]<[/tex] and [tex]>[/tex] use open circle at its end

So, we have:

[tex]f(x) = -1,\ \ \ \ x < -1[/tex]

The line stops at -1 with an open circle      

[tex]f(x) = 0,\ \ \ \ -1 \le x \le 1[/tex]

The line starts at - 1 and stops at -1 with a closed circle at both ends

[tex]f(x) = 1,\ \ \ \ x > 1[/tex]

The line starts at 1 with an open circle

The options are not complete, so I will plot the graph myself.

See attachment for graph

Answer:

6v(2v+3)2)7（-5v-8）

6v+2v-5v+3+2-8

3v-3

The question is incomplete. The complete question is :

A lottery offers one $800 prize, one $700 Prize, two $800 prizes, and four $100 prizes. One thousand tickets are sold at $5 each. Find the expectation if a person buys two tickets. Assume that the player's ticket is replaced after each draw and that the same ticket can win more than one prize. Round to two decimal places for currency problems.

The expected if a person buys two tickets is $__

Answer:

$ -1.52

Step-by-step explanation:

Given :

A lottery offers --

One $800 prize

One $700 prize

Two $800 prize

Four $100 prizes

Let X = net win

    X          P(X)

  795      1/1000

  695      1/1000

  795      2/1000

   95      4/1000

    -5     996/1000

[tex]$E(X) = \sum X \ p(X)$[/tex]

         [tex]$=795 \times \frac{1}{1000} + 695 \times \frac{1}{1000} + 795 \times \frac{2}{1000} + 95 \times \frac{4}{1000} + (-5) \times \frac{996}{1000}$[/tex]

         = 0.795 + 0.695 + 1.59 +  0.38 - 4.98

         = $ -1.52

Answer:

95 truckloads

Last truck = 10 cars

Step-by-step explanation:

Capacity of auto truck = 12 cars

Total number of cars to be brought in = 1150

The number of truckloads required :

Total number of cars to be brought in / capacity of auto truck

Number of truckloads = 1150 / 12 = 95.83333

This means that the number of full truckloads required will be, the whole number = 95

The last truck won't be full and will contain :

1150 - (95 * 12)

1150 - 1140

= 10 cars

Answer:

[tex]\frac{da}{dt}=-95.2m/s^2[/tex]

Step-by-step explanation:

From the question we are told that:

Slant height [tex]h=13ft[/tex]

Velocity [tex]v=\frac{dx}{dt}=8[/tex]

Distance [tex]d=12ft[/tex]

Generally the equation for area is mathematically given by

[tex]A=0.5*x*sqrt(169 - x^2)[/tex]

Differentiating

[tex]\frac{da}{dx}=\frac{169-2 x^2}{(2 sqrt(169-x^2))}[/tex]

Multiplying through by dx/dt

[tex]\frac{da}{dx}*\frac{dx}{dt}=\frac{169-2 x^2}{(2 \sqrt{169-x^2})}*\frac{dx}{dt}[/tex]

[tex]\frac{da}{dt}=\frac{169-2x^2}{(2 \sqrt{169-x^2})}*\frac{dx}{dt}[/tex]

[tex]\frac{da}{dt}=\frac{169-(2*12^{2})}{2*\sqrt{(169-12^{2})}}*8[/tex]

[tex]\frac{da}{dt}=-95.2m/s^2[/tex]

Since the state is broken up into counties, and each county subdivided into precincts, this provides a natural way to form cluster samples.

If the precinct populations are too large, then you can further subdivide based on household or building residence. In other words, you can randomly select a building and consider that a separate cluster. All residents of that building would be part of the cluster.

In cluster sampling, the idea is that whichever clusters you select, you survey every person who resides in that cluster. So naturally you need to be careful not to go overboard.

Answer:

Need to see the problem, but the "zero of the function" is the x value when y=0.

Substitute '0' for y.

Solve for x

Answer: D

Step-by-step explanation: