A national consumer agency selected independent random samples of 45 owners of newer cars (less than five years old) and 40 owners of older cars (more than five years old) to estimate the difference in mean dollar cost of yearly routine maintenance, such as oil changes, tire rotations, filters, and wiper blades. The agency found the mean dollar cost per year for newer cars was $195 with a standard deviation of $46. For older cars, the mean was $286 with a standard deviation of $58. Which of the following represents the 95 percent confidence interval to estimate the difference (newer minus older) in the mean dollar cost of routine maintenance between newer and older cars?
A. (195 - 286) + 1.992 underroot46/45 + 58/40
B. (286 - 195) + 1.992 underroot46^2/45+ 58^2/40
C. (195 - 286)+ 1.992 underrot 140² 158²/45+40
D. (286 - 195) + 1.992 46 1582 45 +40
E. (195-286) +1.992 462 + 58 45 40

Answer:

Step-by-step explanation:

Answer:

Your answer would be 20 not 10

Step-by-step explanation:

trust me i took the test

Answer:

-9.

The product of -9 and -8 is 72.

Step-by-step explanation:

Product means the answer of a multiplication, so we're given 72 and -8.

We can solve this by using inverse operations.

The inverse operation of multiplication is division, so we divide 72÷ -8

This will give us -9.

Step-by-step explanation:

The given equations are :

2x+ y =5 ....(1)

5x+3y = 12

We need to find the matrix equation that represents the system of equations.

[tex][A]=\left[\begin{array}{cc}2&1&\\5&3\end{array}\right][/tex]

[tex][B]=\left[\begin{array}{cc}5\\12\end{array}\right][/tex]

And

[tex][X]=\left[\begin{array}{cc}x\\y\end{array}\right][/tex]

Hence, the matrix equation is :

[tex]\left[\begin{array}{cc}2&1&\\5&3\end{array}\right] \left[\begin{array}{cc}x\\y\end{array}\right]=\left[\begin{array}{cc}5\\12\end{array}\right][/tex]

Hence, the correct option is (b).

Answer:

.375

Step-by-step explanation:

Answer: 0.375

Step-by-step explanation:

Hey there! If you have any questions feel free to leave them in the comments below.

To find the answer you would divide the numerator by the denominator. [tex]\frac{3}{8}[/tex] would be equal to 0.375

~I hope I helped you :)~

Answer:

The original price of the lawnmower is $ 1,528.

Step-by-step explanation:

If Reid's Hardware makes a 9% discount on cash payments, and Trey paid $ 1,390.49 for his lawnmower, to determine the initial cost of the same, the following calculation must be performed:

100 - 9 = 91

91 = 1,390.49

100 = X

(100 x 1,390.49) / 91 = X

139.049 / 91 = X

1.528 = X

Thus, the original price of the lawnmower is $ 1,528.

Answer:

(-7) (-10x - 3y = -18)

(10) (-7x - 8x = 11)

--------------------------

70x + 21y = 126

+ -70 - 80x = 110

---------------------------

-59x = 236

x = -4

Answer

[tex] \huge{ \boxed{ \text{(3 \:, - 4)}}}[/tex]

✑ [tex] \underline{ \underline{ \text{First ,\: let's \: know \: about \: elimination \: method}}}[/tex] :

☇ In this method , we add or subtract the given equations to eliminate one of the two variables by making their coefficients equal. Then , a single equation with one variable so obtained is solved to find the value of the variable. The value of the variable is substituted to any one equation to find the value of the eliminated variable.

☯ [tex] \underline{ \underline{ \text{Let's \: solve}}} : [/tex]

[tex] \underline{ \text{Original \: system}} : [/tex]

[tex] \text{ - 10x - 3y = - 18 - - - - Equation\: (i)}[/tex]

[tex] \text{ - 7x - 8y = 11 - - - - Equation \: (ii)}[/tex]

[tex] \text{Step \: 1} : [/tex] Take L.C.M ( Lowest Common Multiple ) of 10 and 7. For this , find the prime factors of each number. Then, take out the common prime factors and other remaining prime factors and multiply them.

L.C.M = Common factors × Remaining Factors

= 1 × 2 × 5 × 7

= 70

[tex] \text{Step \: 2} : [/tex] Multiply equation ( i ) by 7

[tex] \text{7( - 10x - 3y ) = - 18  * 7}[/tex]

⇢ [tex] \text{ - 70x - 21y = - 126 - - - - equation \: (iii)}[/tex]

[tex] \text{Step \: 3} : [/tex]Multiply equation ( ii ) by 10

[tex] \text{10( - 7x - 8y) = 11 \: * \: 10}[/tex]

⇢ [tex] \text{ - 70x - 80y = 110 - - - - equation \: (iv)}[/tex]

[tex] \text{Step \: 4} : [/tex] Subtract equation ( iv ) from equation ( iii ) :

Also Remember that while subtracting , sign of each term of the second equation changes. Here , we are eliminating x . So to make the coefficient of y same , equation ( i ) is multiplied by 7 and equation ( ii ) is multiplied by 10.⇩

[tex] \text{ - 70x - 21y = - 126}[/tex]

[tex]\text{+70x + 80y = - 110}[/tex]

___________________

[tex] \text{ \: \: \: \: \: \: 59y = - 236}[/tex]

Solve :

⇢ [tex] \text{59y/59 = - 236/59}[/tex]

⇢ [tex] \boxed{ \bold{ \text{y = - 4}}}[/tex]

[tex] \text{Step \: 5} : [/tex]

Substitute the value of y into equation ( iii ) , we get :

[tex] \text{ - 70x - 21y = - 126}[/tex]

➳ [tex] \text{ - 70x - 21( - 4) = - 126} [/tex]

➳ [tex] \text{ - 70x - ( - 84) = - 126} [/tex]

➳ [tex] \text{ - 70x + 84 = - 126}[/tex]

➳ [tex] \text{ - 70x = - 126 - 84}[/tex]

➳ [tex] \text{ - 70x = - 210}[/tex]

➳ [tex] \text{ - 70x/  - 70 = - 210/  - 70}[/tex]

➳ [tex] \boxed{ \bold{ \text{x = 3}}}[/tex]

[tex] \bold{ \underline{ \text{Hence ,\: x = 3 \: and \: y = - 4}}}[/tex]

Hope I helped!

♡ Have a wonderful day / night ツ

~ [tex] \sf{TheAnimeGirl} [/tex] ♪

▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

Answer:

18

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Step-by-step explanation:

Step 1: Define

4a - 2

a = 5

Step 2: Evaluate

Answer:

The card "4a-2" is equal to 18

4a-2 = 18

Step-by-step explanation:

#1. Replace a with 5 and Your equation should look like the following:

4(5)-2

#2. Now Simplify, we all know that multiplication goes before subtraction or addition:

20-2

#3. Celebrate:

18

Woohoo

Hope this helps!

Have a nice day!

If you find my answer helpful

Pls consider marking my answer as Brainliest! It would mean a lot!

Answer:

x=30

Step-by-step explanation:

set the sum of both equal to 180 bc it makes a straight line

(x-1)+(5x+1)=180

add and subtract 1 from each side

x+5x=180

add like terms

6x=180

divide by 6

x=30

Answer:

D: x=30

Step-by-step explanation:

(x-1)⁰+ (5x+1)⁰=180⁰

x-1+5x+1=180

x+5x-1+1=180

6x=180

x=30

Answer:0.98

hope this helps have a good day

Step-by-step explanation:

Answer:

speed i answerd first U.U

Step-by-step explanation:

Answer:

im pretty sure its a

Step-by-step explanation:

Answer:

x = -1, 0, 1, 2, 3, 4

y = 3, 2, 1, 0, -1, -2

Answer:

x = -1, 0, 1, 2, 3, 4

y = 3, 2, 1, 0, -1, -2

Answer:

[tex] - 23[/tex]

Step-by-step explanation:

Substitute -3 for X in the expression then solve.

Answer:

-23

Step-by-step explanation:

They give us the variable's value, which is [tex]x=-3[/tex]. All we have to do from here is plug it into the expression that they gave us!

So, let's do exactly that! The expression that they gave us is [tex]5x-8[/tex], and we know the value of x because they gave it to us!

Let's plug it in.:

[tex]5(-3)-8[/tex]

Let's follow P.E.M.D.A.S. and our order of operations to determine what to do first. Since we have multiplication going on within parenthesis, let's do that first.

[tex]5(-3)=-15[/tex] because a negative number times a positive number equates to a negative number. Now, we have the following expression: [tex]-15-8[/tex]

Let's subtract this now! Remember, subtracting a number from another number is basically adding the opposite of the second number; essentially, you're following keep, change, flip. You keep the first number without doing anything to it, you change the sign of the operation, and you flip the sign of the 2nd number. Let's revise this problem now with these rules.: [tex]-15 + (-8)[/tex], now we have something that we can work with! Since both numbers are negative and are being added, we keep the sign, and just add their absolute value, leaving us with the expression being -23.

Answer:

Yes

Step-by-step explanation:

Lisa and Frank type at the same rate.

They both type 1 page every six minutes.

Lisa types 6 pages every 36 minutes, and if we divide the minutes by the pages, we get

[tex]\frac{36}{6} = 6[/tex]

And Frank types 5 pages ever 30 minutes, when we divide we get

[tex]\frac{30}{5} = 6[/tex]

Answer:

Step-by-step explanation:

1. Write the equation in point slope form. Remember, point slope form looks like this: y-y1=m(x-x1), with m representing slope. With this equation, you plug in the y coordinate for y1 and the x coordinate for x1. So, it will look like this

y+6=2/3(x+5)

2. Then, convert that into slope intercept form, which is y=mx+b.

y+6=2/3x+10/3 (2/3 * 5)

y= 2/3x - 8/3 (10/3 - 6)

Therefore, your slope-intercept form of the equation is: y=2/3x - 8/3

3. From there, you can graph the line. See the graph in the image attached.

4 is correct

reason is because the number next to x is the constant number and the end number is where you started

9514 1404 393

Answer:

  g(x) = f(x -2) -1

Step-by-step explanation:

The transformation g(x) = f(x -h) +k causes the graph of function f(x) to be translated h units to the right and k units up. Here, g is translated 2 units right and 1 unit down, so (h, k) = (2, -1). The translated function is ...

  g(x) = f(x -2) -1

Answer:

b.  A list of credits and debits made during the period.

Step-by-step explanation:

Edge 2021

On a monthly account statement, what you are expected to find is a  A list of credits and debits made during the period.

This can be referred to as a statement of the debits and the credits that occurred in a given period of one month.

The account statement is a statement of the transactions that have occurred in an establishment over a period.

Read more on account statements here:

https://brainly.com/question/24498019

#SPJ9

Answer:

C: 12x squared

Step-by-step explanation:

the equation would look like [tex]2x^{2}[/tex] · [tex]6[/tex] or [tex]6(2x^{2})[/tex]

you only multiply the coefficients, leave the exponent alone for this one

so 2 times 6 would be 12 and the [tex]x^{2}[/tex] remains the same giving you [tex]12x^{2}[/tex]

Answer: Hello!

Step-by-step explanation:

Your answer would be D :)

Solution :

Number of different samples of two technicians possible is = 10, as 2 technicians are to be chosen from a total of 5 technicians.

a). Therefore, 10 different samples are possible of size two.

b).

        Sample                    Shut down         Mean

1. Taylor, Hurley                 4, 3                    3.5

2. Taylor, Gupta                 4, 5                    4.5

3. Taylor, Rousche             4,6                      5

4. Taylor, Huang                4, 3                    3.5

5. Hurley, Gupta                 3,5                       4

6. Hurley, Rousche             3,6                      4.5

7. Hurley, Huang                 3,3                       3

8. Gupta, Rousche              5,6                       5.5

9. Gupta, Huang                  5,3                       4

10. Rousche, Huang            6,3                      4.5  

                                                                        42

Now mean of sample means  [tex]$=\frac{42}{10}$[/tex]    = 4.2

Mean of population is = [tex]$\frac{4+3+5+6+3}{5}$[/tex]    = 4.2

Thus both the means are equal.

Answer:

A and B

Step-by-step explanation:

The original equation simplifies down to -4m - 2

Answer A and B also simplify down to -4m -2, and therefor are equivalent

A: -2(4m + 1) + 4m

-8m - 2 + 4m

-4m - 2

B: 2(2m - 1) - 8m

4m - 2 - 8m

-4m - 2

Answer:

$4.911  million or  $6.481 million

Thus, we are 95% confident that the mean amount of all venture-capital investments in the high-tech industry is somewhere between $4.911 million and $6.481 million.

Step-by-step explanation:

Given that:

sample size n = 18

standard deviation σ = 1.70

confidence interval = 95%

Sample mean [tex]\overline x =\dfrac{ \sum x }{n}[/tex]

[tex]\overline x =\dfrac{ 102.52 }{18}[/tex]

[tex]\overline x =[/tex] 5.696

The level of significance = 1 - C.I

= 1 - 0.95

= 0.05

The critical value of [tex]Z_{\alpha/2} = Z_{0.025} = 1.960[/tex] from the Z tables

The 95% C.I for the mean is;

[tex]= \overline x \pm Z_{\alpha/2} \times \dfrac{\sigma}{\sqrt{n}}[/tex]

[tex]=5.696 \pm 1.960 \times \dfrac{1.70}{\sqrt{18}}[/tex]

[tex]=5.696 \pm 1.960 \times \dfrac{1.70}{4.243}[/tex]

[tex]=5.696 \pm 1.960 \times 0.4007[/tex]

= 5.696 ± 0.785372

= (5.696 - 0.785372 , 5.696 + 0.785372 )

= ( 4.910628 , 6.481372  )

≅ $4.911  million or  $6.481 million.

Thus, we are 95% confident that the mean amount of all venture-capital investments in the high-tech industry is somewhere between $4.911 million and $6.481 million.

Answer:

48$

Step-by-step explanation:

80% of 80 is 64 which means she spent 16$ and saved 64$

so 64-16=48$

answer = 48$

Answer: the answer is no :)