A researcher wishes to estimate within $5 the average repair cost of for a refrigerator. If she wishes to be 90% confident, how large of a sample would be necessary if the population standard deviation is $15.50?

Answer:

-15

Step-by-step explanation:

Answer:

$0.36

Step-by-step explanation:

Let the cost per unit of electricity  = e

Let the cost per unit of gas  = g

  a homeowner used 600 units of electricity and 100 units of gas for a total cost of 390;

   600e + 100g  = 390  ----- i

  400 units of electricity and 250 units of gas were used for a total cost of $326.

     400e + 250g  = 326 ----- ii

Now we have two equations, and we solve for g;

     600e + 100g  = 390  ----- i

     400e + 250g  = 326 ----- ii  

Multiply equation i by 4 and equation ii by 6;

    2400e + 400g  = 1560 ---- iii

    2400e + 1500g  = 1956 ---- iv

Subtract equation iii from iv;

                  1100g  = 396

                       g  = [tex]\frac{396}{1100}[/tex]   = 0.36

Cost per unit of gas $0.36

The solution is option C.

In mathematics, multiplication is a method of finding the product of two or more numbers. It is one of the basic arithmetic operations, that we use in everyday life.

here, we have,

(-8)(-12)(2)

=96*2

=192

so. we get,

It would be c because when you multiply 8 and 12 you get 96 and when you multiply 96x2 you get 192 .

so, therefore your answer is c.

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Answer:

D

Step-by-step explanation:

Look at the y-values for both dots, the open circle is -7 and the closed circle is 5. The closed circle means y is going to be equal to, so the greater than sign is made to be equal.

Answer:

The equation is y = -5x - 1.

Step-by-step explanation:

1. Find the slope using the formula. Slope = (4 + 1) / (-1 - 0) which is equal to 5 / -1 which is -5.

2. Use the slope-point formula to construct an equation. The equation is y - 4 = -5 * (x + 1)

3. Simplify. We would get y = -5x - 5 + 4, which is y = -5x - 1.

Answer: The equation is y = -5x - 1.

Answer:

B

Step-by-step explanation:

Part A:

3(m+54) = 381 shows that 54 is being added to m, the initial sum. Then it shows the sum of 54 + m being multiplied by 3 to get to the new balance of $381. This equation most accurately matches with the question.

Part B:

3(m-54) = 381.

You would first divide both sides by 3.

m - 54 = 127

You would now add 54 to both sides.

You now know m = 181.

Answer:

20ft²

Step-by-step explanation:

Let the length = L

Let the width = W

Perimeter of a rectangle = 2L + 2W

Translating the word problem into an algebraic equation, we have;

L = 5W .......equation 1

2L + 2W = 24 ........equation 2

To find the width

Substituting equation 1 into equation 2, we have;

2(5W) + 2W = 24

10W + 2W = 24

12W = 24

W = 24/12

Width, W = 2 ft

To find the length;

Substituting the value of "W" into equation 1, we have;

L = 5W

L = 5*2

L = 10 ft

To find the area of the rectangle;

Area = LW

Area = 10*2

Area = 20 ft²

Therefore, the deck's area is 20 feet square.

Answer:

D

Step-by-step explanation:

Answer:

ok so the odd one out is A) the measure of <ahd is 30°

Step-by-step explanation:

external angle is equal to the sum of the two interior angles on the opposite side

3x= x +15 +x +15

3x=x+x+15+15

3x= 2x +30

3x-2x= 30

x = 30

Answer:

6+y

Step-by-step explanation:

simple:)

Answer:

I have no idea

Step-by-step explanation:

Answer: y= -6/5x-2

Step-by-step explanation:

That’s wut it said

Answer:

Step-by-step explanationjiuijkk8

u:

Answer:

the unit rate for each pair is $1.13

Step-by-step explanation:

Okay this is how you would do this problem correctly:

we know that 4 dozen pairs of gloves cost $54.24 however we want to know what the cost is for one pair so we have to make a equation by dividing total cost by the number of glove pairs.

$54.24/4 dozen

the reason we are putting 4 dozen instead of just dividing $54.24 by 4 is because we want to know the unit price for each pair of gloves so it would actually look like this:

$54.24/4(12)

Dozen = 12

so we multiply 12 by 4 to get 48 pairs of gloves, we then divide $54.24 by 48 to find our unit rate of pricing for each pair:

$54.24/48 = 1.13

so now we place a dollar sign in front of 1.13 to get your answer:

for every pair bought it costs $1.13

So how did the Analysis A contractor get the wrong answer? well when she had bought the 4 dozen gloves she divided $54.24 by 4, which in this case would make it seem as though the gloves came in a 12 pack of gloves. However she was buying the gloves individually so she would have to multiply 4 by 12 before dividing the total number of gloves from $54.24.    

Answer: the parenthesis: (44-4)

Step-by-step explanation: In order of operations parenthesis are always first. Then exponents, then multiplication and division, and then addition and subtraction. (PEMDAS)

Answer:

c is the correct answer

Step-by-step explanation:

Answer:

1/5688x-18

I am not sure about my answer because I think the question is missing some information but my answer is 1/5688x-18. Thanks!

The number of miles that farther you have to walk will be 1/12 miles.

The analysis of mathematical representations is algebra, and the handling of those symbols is logic.

PEMDAS rule means for the Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This rule is used to solve the equation in a proper and correct manner.

You are walking from home to the music store. You stop for a rest after 2/3 miles. The music store is actually 3/4 miles from home.

The number of miles that farther you have to walk will be

⇒ 3/4 - 2/3

⇒ (9 - 8) / 12

⇒ 1/12

The number of miles that farther you have to walk will be 1/12 miles.

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Answer:

2.5 cups in each jar

Step-by-step explanation:

10/4 is 2.5

Answer:

The dimension of the triangle is 4.144 m and the dimension of the square is 2.392 m

Step-by-step explanation:

let a side of the equilateral triangle = x

let a side of square = y

3x + 4y = 22

4y = 22 - 3x

[tex]y = \frac{11}{2} -\frac{3x}{4}[/tex]

subjective function, the total area is given by;

[tex]f(x,y) = \frac{x^2\sqrt{3} }{4} +y^2[/tex]

[tex]f(x) = \frac{x^2\sqrt{3} }{4} + (\frac{11}{2} -\frac{3x}{4})^2\\\\f(x) = \frac{x^2\sqrt{3} }{4} +\frac{121}{4} -\frac{33x}{4} +\frac{9x^2}{16} \\\\f(x)' = \frac{x\sqrt{3} }{2} -\frac{33}{4} +\frac{9x}{8} \\\\\frac{x\sqrt{3} }{2} -\frac{33}{4} +\frac{9x}{8}=0\\\\\frac{x\sqrt{3} }{2} + \frac{9x}{8} =\frac{33}{4}\\\\\frac{4x\sqrt{3} +9x}{8} = \frac{33}{4}\\\\4x\sqrt{3} +9x = 66\\\\x(4\sqrt{3} +9) = 66\\\\x(15.928) = 66\\\\x = \frac{66}{15.928}\\\\x = 4.144 \ m[/tex]

solve for y

[tex]y = \frac{11}{2} -\frac{3x}{4}\\\\y = \frac{11}{2} -\frac{3*4.144}{4}\\\\y = 5.5-3.108\\\\y = 2.392 \ m[/tex]

Therefore, the dimension of the triangle is 4.144 m and the dimension of the square is 2.392 m

Answer: A Only

Step-by-step explanation:

To determine that a linear model is appropriate, the residual plot should be randomly dispersed.

Answer:

1

Step-by-step explanation:

Answer: Hope this helps!!!

Step-by-step explanation:Absolute Value: You need to find how far away both numbers are from zero, then add these values together to see how far apart these numbers. The absolute value of nine, |-9| is 9, and |12| is 12. This means that the nine is nine spots away from zero, and twelve is twelve spots from zero. This means that the numbers are 20 units from each other.

Distance -9 is from 12 You need to find how much of an increase from nine you need to reach the twelve. So -9 + ? = 12. What number can you add to equal twelve? You can add 20 to make the equation true. (? = 20) The distance from -9 to 12 is a positive 20.

Distance from 12 to -9 This is similar to the previous example. What number can you insert to make the 12 equal the negative nine? 12 - ? = -9. The number would be -20, which means that 12 is 20 spots away from the negative nine, as it took at negative twenty to get us to the negative nine.

Answer:

Step-by-step explanation:

Given

Lambert family uses up a 1/2

gallon jug of milk every 3 days.

rate drink milk per day

Solution =1/2÷3

= 1/6

So the answer is 1/6

Answer:

the next number is 6

Step-by-step explanation:

i'm assuming you want to find what comes next after 25 so pretty much each number decreases by 19

The 10th term of the arithmetic sequence will be –89.

Let a₁ be the first term and d is the common difference between the terms. Then the nth term will be given as

[tex]\rm a_n = a_1 + (n - 1)d[/tex]

The sequence is given below.

82, 63, 44, 25, ......

The first term is 82 and the common difference will be

d = 63 – 82

d = –19

Then the equation will be

[tex]\rm a_n =82- (n - 1) \times 19[/tex]

Then the 10th term of the sequence will be

a₁₀ = 82 – (10 – 1) x 19

a₁₀ = 82 – 171

a₁₀ = –89

The complete question is 82 63 44 25 sequence. What is the 10 term of the sequence?

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Answer:

sarah makes 10 cupcakes

Step-by-step explanation:

baker makes 30 cupcakes.

30/3=10

Answer: D. minimizes the sum of the squared residuals

Step-by-step explanation: The ordinary least square method is often used in locating the trendine which best fits a graphical linear model. The best is one in which the sum of the squared residual is smallest. The residual refers to the difference between the actual and the predicted points. The sum of the squared differences is obtained and the trend line is positioned where the residual is minimum. Choosing a OLS, and minimizing the sum.of the squared residual, the error difference between the predicted and actual score is minimized or reduced, hence, improving the prediction accuracy of our model.

Answer:

They're perpendicular

Step-by-step explanation:

Cause they interfere the point (47/65, 66/65) in a 90 degree angle

Answer:

If neither of the two real numbers is zero, then their product is also not zero Suppose also that x is a real number that satisfies the equation The " / " symbol does not always give you a result of an integer, so be careful.pkek, and any other expression for n as a product of prime numbers is identical to this except,.

Step-by-step explanation:

Answer:

The probability that the sample mean will be between 25.5 and 27 years is 0.1359.

Step-by-step explanation:

Let X denote of age of JSOM students.

The information provided is:

[tex]\mu=24\\\sigma=9\\n=36[/tex]

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

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

[tex]\mu_{\bar x}=\mu\\[/tex]

And the standard deviation of the sample means is given by,

[tex]\sigma_{\bar x}=\frac{\sigma}{\sqrt{n}}[/tex]

As the sample size is large, i.e. n = 36 > 30, the sampling distribution of the average age of all the JSOM students can be approximated by the normal distribution.

Compute the probability that the sample mean will be between 25.5 and 27 years as follows:

[tex]P(25.5<\bar X<27)=P(\frac{25.5-24}{9/\sqrt{36}}<\frac{\bar X-\mu_{\bar x}}{\sigma_{\bar x}}<\frac{27-24}{9/\sqrt{36}})\\\\=P(1<Z<2)\\\\=P(Z<2)-P(Z<1)\\\\=0.97725-0.84134\\\\=0.13591\\\\\approx 0.1359[/tex]

Thus, the probability that the sample mean will be between 25.5 and 27 years is 0.1359.