At the pet fair, Darlene’s dog
weighed 5 times as many pounds
as Leah’s dog. Together, the dogs
weighed 60 pounds.
How many pounds does Leah’s
dog weigh?

Answer:

90

Step-by-step explanation:

Step-by-step explanation:

Given - In selecting a sulfur concrete for roadway construction in regions that experience heavy frost, it is important that the chosen concrete has a low value of thermal conductivity in order to minimize subsequent damage due to changing temperatures. Suppose two types of concrete, a graded aggregate and a no-fines aggregate, are being considered for a certain road. The table below summarizes data on thermal conductivity from an experiment carried out to compare the two types of concrete.

Type            ni                xi                  si

Graded       42           0.486            0.187

No-fines      42           0.359           0.158

To find - a. Formulate the above in terms of a hypothesis testing problem.

b. Give the test statistic and its reference distribution (under the null hypothesis).

c. Report the p-value of the test statistic and use it to assess the evidence that this sample provides on the scientific question of difference in mean conductivity of the two materials at the 5% level of significance.

Proof -

a.)

Hypothesis testing problem :

H0 : There is significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.

H1 : There is no significant difference between mean conductivity for the graded concrete and mean conductivity for the no fines concrete.

b)

Test statistic :

[tex]Z = \frac{x_{1} - x_{2} }{\sqrt{\frac{s_{1} ^{2} }{n_{1}} + \frac{s_{2}^{2} }{n_{2}} } }[/tex]

[tex]Z = \frac{0.486 - 0.359 }{\sqrt{\frac{0.03496 }{42} + \frac{0.02496 }{42} } }[/tex]

[tex]Z = \frac{0.127 }{\sqrt{0.001468}}[/tex]

[tex]Z = \frac{0.127 }{0.0377}[/tex]

⇒Z(cal) = 3.3687

Z(tab) = 1.96

As Z (cal) > Z(tab)

So, we reject H0 at 5% Level of significance

p-value = 0.99962

Hence

There is significant difference in mean conductivity at the two materials.

Answer:

345 - 40% = 207$

Step-by-step explanation:

(345 - 30%) - 15% = 205.3 (Better deal)

Answer:

30% off and additional 15% at the register

Step-by-step explanation:

Deal 1

$345 × 40% = $138

$345 - $138 = $207

Deal 2

$205.30

Answer:

top and bottom

Step-by-step explanation:

Answer:

They are all correct.

Step-by-step explanation:

1.

1/2(b)(h)

1/2(4)(6)

1/2(24)

12

2. l x w

7 x 5

35

3. (b)(h)

(8)(4)

32

Answer:

Semiconductors are somewhere in-between conductors and insulators. This means that they are specific when it comes to conducting electricity meaning that their conduction of electricity varies based on their condition at the time.

For instance, they can conduct electricity when heated.

Properties:

    1. Perfect insulator at Absolute Zero.

As mentioned above, semi conductors are better at conducting electricity when they are heated. At Absolute zero - the lowest temperature possible -  therefore, these materials would conduct absolutely no electricity thereby making them perfect insulators.

   2. More resistance than Conductors but less than Insulators

As mentioned above, they have properties in-between those of insulators and conductors. One of those is their resistance. They can resist more than conductors but less than insulators.

It's B because 2 equals 86 dgrees since its vertical angles

Answer:

C

Step-by-step explanation:

You take the points and input them into the equation. If they all equal the set then it is the equation. So for example a point on the graph is (2,30) so in this case x is 2 so you would do y= 15(2) which is 30. So that equation and point checks out. Repeat with the others

Answer:

its c

Step-by-step explanation:

:)

Answer:

If the goal is to break the vases: 3/20 = 15.0% or 0.15

If the goal is to not break the vases: 17/20 = 85.0% or 0.85

Answer:

It can't be simplified or added together because one is multiplied by x and the other is not

Step-by-step explanation:

Answer: Area of the shape is 168 ft.

Step-by-step explanation: Split the shape into 2 shapes: A rectangle and a triangle.

Area of the rectangle shape is 144 and the area of the triangle is 24. Add them and you get 168.

Answer:

i think B

Step-by-step explanation:

Answer:I think 3 years

Step-by-step explanation:

sorry if im wrong

Answer:

1568

Step-by-step explanation:

The computation of the minimum sample size is shown below:

Given that

Error E = 11

The population standard deviation [tex]\sigma[/tex] =217

Confidence level 1-α = 95%

Now following formula should be used

n > (Zalpha ÷ 2 × sigma ÷ E)^2

As we know that

Zalpha ÷ 2= 1.96

Now the sample size is

n> (1.96 × 202  ÷ 10)^2

= 1568

Answer:

B. 5(2x+5)

Step-by-step explanation:

Factor 5 out of 10x+25. and you get 5(2x+5)

Answer:

B. 5(2x + 5

Step-by-step explanation:

If you have any questions feel free to ask in the comments

Answer:

My best guess is D she can make 4 dozen cokies

Step-by-step explanation:

Answer:

B

Step-by-step explanation:

it is B because  for number A 1+1 =2 2>1.75.  B= 1.5<175, c= 0.5 <1, d. 2>1.75

Answer: 4x^2

Step-by-step explanation: Multiply that by -1 to get -4x^2 and multiply by 7x to get 28x^3

Answer:

The number of required shelves is 5

You have to find the HCF of 45, 105, and 75.

Answer:

No, there is not sufficient evidence to support the claim that the bags are underfilled

Step-by-step explanation:

A manufacturer of potato chips would like to know whether its bag filling machine works correctly at the 434 gram setting.

This means that the null hypothesis is:

[tex]H_{0}: \mu = 434[/tex]

It is believed that the machine is underfilling the bags.

This means that the alternate hypothesis is:

[tex]H_{a}: \mu < 434[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

434 is tested at the null hypothesis:

This means that [tex]\mu = 434[/tex]

A 9 bag sample had a mean of 431 grams with a variance of 144.

This means that [tex]X = 431, n = 9, \sigma = \sqrt{144} = 12[/tex]

Value of the test-statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{431 - 434}{\frac{12}{\sqrt{9}}}[/tex]

[tex]z = -0.75[/tex]

P-value of the test:

The pvalue of the test is the pvalue of z = -0.75, which is 0.2266

0.2266 > 0.01, which means that there is not sufficient evidence to support the claim that the bags are underfilled.

Answer:

The number of milk chocolate pieces is between 115 and 120 pieces.

Step-by-step explanation:

Answer:

53

Step-by-step explanation:

106 miles per hour would get him home in 1 hour but it takes 2 hours so you can divide 106 by 2 to 53 miles per hour.

Answer:

2x-7

Step-by-step explanation:

Answer:

Step-by-step explanation:

There are several sort of "obvious" properties of equality/congruence. Keeping them sorted out can be a bit of a trick.

  A = A . . . . reflexive property

  A = B ⇔ B = A . . . . symmetric property (erroneously cited in the proof)

  A = B, B = C ⇒ A = C . . . . transitive property (the one needed in the proof)

__

Not to confuse the issue, but there is also the "substitution property of equality" that says if X = Y, then X can be substituted for Y or vice versa. In the end, the transitive property is an application of this, where we're substituting for B in the second equation, or for A in the first equation.

The A=B=C form of Statement 1) in the proof is what gives you the clue it is the transitive property that is wanted here.

Answer:

54= 15 + J

Step-by-step explanation:

j= 39

Step-by-step explanation:

Step 1: Calculate the mean. Step 2: Calculate how far away each data point is from the mean using positive distances. These are called absolute deviations. Step 3: Add those deviations together. Step 4: Divide the sum by the number of data points.

Answer:

I dont know I am sorry I really had to ask a question and i don't have enough points so sorry you can report me if you want but I really need some

Answer:

x-30

Step-by-step explanation:

Answer: 5(x-2)=40     5x-10 = 40      5x=50    x=10  

Step-by-step explanation:

^

Answer : 169

Step-by-step explanation:

4(x+19) = 752

4x +76 = 752

4x = 752 - 76

x = 676/4

x=169

Hope this helps ;)

Please mark me the BRAINLIEST

9514 1404 393

Answer:

  x^2 +(y -61)^2 = 625/36

Step-by-step explanation:

The graph of the above equation is attached.

If the circumference of the wheel is 25π/3 feet, the diameter is ...

  d = C/π = (25/3π)/π = 25/3 . . . feet, about 8.33 feet

The radius will be half that value, or 25/6 feet.

For a center point (h, k) and radius r, the equation of a circle is ...

  (x -h)^2 +(y -k)^2 = r^2

You want the center to be more than 60 feet from the ground, so we can make it be 61 feet. The horizontal location is not specified, so we can make it zero.

This means we apparently want the equation for a circle of radius 25/6 feet with a center that is (x, y) = (0, 61). The equation of this circle is ...

  x^2 +(y -61)^2 = 625/36

Answer:

See explanations below

Step-by-step explanation:

Using the coordinate points in the table (0, 4) and (2, 9)

Slope m = y2-y1/x2-x1

m = 9-4/2-0

m = 5/2

slope = 5/2

Get the y-intercept

Substitute m = 5/2 and (0,4) into y = mx+c

4 = 5/2(0) + c

4 = 0+c

c = 4

y-intercept is 4

Get the equation

Recall that y = mx+c

y = 5/2x + 4

Using another 2 points (2,9) and (4, 14)

Slope = 14-9/4-2

Slope = 5/2

Since the slope is the same for the coordinates, hence the the equation is correct