Can someone help please !! I appreciate it

Answer:

b. Mean = 1.6 years, standard deviation - 0.92 years, shape: approximately Normal.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

Subtraction of normal Variables:

When we subtract normal variables, the mean is the subtraction of the means, while the standard deviation is the square root of the sum of the variances.

A consumer group has determined that the distribution of life spans for gas ranges (stoves) has a mean of 15.0 years and a standard deviation of 4.2 years. Sample of 35:

This means that:

[tex]\mu_G = 15[/tex]

[tex]s_G = \frac{4.2}{\sqrt{35}} = 0.71[/tex]

The distribution of life spans for electric ranges has a mean of 13.4 years and a standard deviation of 3.7 years. Sample of 40:

This means that:

[tex]\mu_E = 13.4[/tex]

[tex]s_E = \frac{3.7}{\sqrt{40}} = 0.585[/tex]

Which of the following best describes the sampling distribution of the difference in mean life span of gas ranges and electric ranges?

Shape is approximately normal.

Mean:

[tex]\mu = \mu_G - \mu_E = 15 - 13.4 = 1.6[/tex]

Standard deviation:

[tex]s = \sqrt{s_G^2+s_E^2} = \sqrt{0.71^2+0.585^2} = 0.92[/tex]

So the correct answer is given by option b.

Answer:

Step-by-step explanation:

2 hours at the speed of 45 mph = 90 miles in 2 hours

He should drive 60 miles per hour to make his speed 60 mph.

Answer:

w = 11

Step-by-step explanation:

add 15 to each side of the equation

w = 15 + (-4)

w = 11

Answer: w=11

Step-by-step explanation:

Answer:

6 ≤ x < ∞

Step-by-step explanation:

interval notation: [6, ∞)

set builder notation: {x|x ≥ 6}

17.5 = x

Step-by-step explanation:

1st you add 85 and 55 since those to angles are congruent (means similar) to 8x

2nd you get 140 after adding then

3rd since the angles are congruent you just divide the 140 by 8 to get the value of x

Answer:

5 x y + 5 x + 4 y + 4

5x(y+1)+4(y+1)

(y+1)(5x+4)

Answer:

Its a

Step-by-step explanation:

Answer:

There are infinitely many solutions.

Step-by-step explanation:

3x + 2y = 7

-9x - 6y = -21

Now multiply the first equation by 3

3 × 3x + 2y = 7 ➡ 9x + 6y = 21 Now subtract second equation from first equation

9x + 6y - 9x - 6y = 21 - 21

0 = 0

The equation has infinitely many solutions meaning whatever value you write instead of x and y there will be solution.

Answer: 6% of profit

Step-by-step explanation:

Find the % of profit

179 500 / 190 270 ≈ 0,94 = 94 %

100% - 94% = 6%

Answer:

-7

Step-by-step explanation:

x-8=-15

x=-7

Answer:

5+4=9

and the second one is right

Step-by-step explanation:

;)

Answer:

the first one is incorrect but the second one is correct!

Step-by-step explanation:

5 + 4 = 9

if you have 5 apples and you want to add 4 more

5 + 1 + 1 + 1 + 1 = 9

Answer:q=0,\:q=-16

Step-by-step explanation:

Answer:

6

Explanation:

substituting- f(x)= (1+2) + 2(1+2) -3

3 + 2(3)-3

3+6-3

=6

HOPE IT HELPS

Answer:

560 cubes

Step-by-step explanation:

Volume of prism: lwh, 7*4*2.5, 70cm!

Volume of cubes: lwh, 0.5*0.5*0.5, 0.125cm!

70cm/0.125cm=560 cubes.

Answer:

560 cubes

Step-by-step explanation:

first solve the volume of the rectangular prism

V = l x w x h

where l is the length

w is the width

h is the height

V = 7 x 4 x 2.5

v = 70 cu cm

then solve the volume of the box

v = e^3

v = 0.5^3

v = 0.125

number of cubes = 70 / 0.125

number of cubes = 560 cubes

Answer:

b

Step-by-step explanation:

Your well wisher

Hope it will be helpful

Answer:

I think it's B.

Step-by-step explanation:

Divide using polynomial division.

x + 1 + 1/ x − 1.

Maybe not 100% sure.

Answer:

Step-by-step explanation:

[tex]3x^4-4y^4\\=(\sqrt{3}x^2)^2-(2y^2)^2)\\=(\sqrt{3}x^2+2y^2)(\sqrt{3}x^2-2y^2)\\=(\sqrt{3} x^{2} +2y^{2} )((3^{\frac{1}{4} } x)^2-(\sqrt{2} y)^{2} )\\=(\sqrt{3} x^{2} +2y^{2} )(3^{\frac{1}{4} } x+\sqrt{2} y)(3^{\frac{1}{4} } x-\sqrt{2} y)[/tex]

b because 90

                  15

                  15

               -_____

                  76.50

Answer:

72= 36 + 2x

Step-by-step explanation:

1 shot= $12

  3 shots= $12×3= $36

$72-$36= $36

2 pills= $36

  1 pill= $36/2=$18

x= $18

72= 36 + (2×18)=

      36 + 36= 72

Answer:

(5,3)

Step-by-step explanation:

Answer:

It is a 25 percent discount

I say this because 90/67.5 equals 75 and 25 + 75 equals what... 100

Answer:

75% off

Step-by-step explanation:

90*.75=67.50

Answer:

1,482 square feet

Step-by-step explanation:

Find total area - 37 x 46 = 1,702

Find area of patio and garden - 16 x 10 = 160 for the patio, 12 x 5 = 60 for the garden

Subtract from total area - 1702 - 160 = 1542, 1542 - 60 = 1,482 sq ft

Answer:

Quantity of  cranberry juice = 95  ml  

Quantity of  orange   juice = 95  ml

Step-by-step explanation:

Step 1

Given ,

We have  80% cranberry juice and  4% of  orange juice.

We have to find how much each should be mixed to make 190 ml of a  60% cranberry-orange juice blend.

Step 2

Let's assume

Quantity of  cranberry juice =x ml  

Quantity of  orange   juice =y  ml  

Then,

x + y = 190

and

x×80100 +y×4100 = 190×60100  

⇒ 0.8x+0.4y = 114    

⇒ 2x+y = 285  

⇒ y = 285−2x  

Step 3

Substituting   y = 285−2x  in  x + y = 190  

⇒ x+285−2x = 190  

⇒ −x = 190−285  

⇒ −x = −95  

⇒ x = 95  ml  

Substituting x = 95   in  x + y = 190

⇒ 95 + y = 190  

⇒ y = 190−95  

⇒ y = 95 ml  

So,

Quantity of  cranberry juice =95  ml  

Quantity of  orange   juice = 95  ml  

Answer:

[tex]\huge\boxed{\sf 168\ in.\²}[/tex]

Step-by-step explanation:

Surface area of the base:

= Length * Length

= 6 * 6

= 36 in.²

Surface Area of 1 Lateral Face:

= [tex]\sf \frac{1}{2} (Base * Height)[/tex]

Base = 6 inches

Height = 11 inches

= 1/2 (6*11)

= 3 * 11

= 33 in.²

Surface Area of 4 lateral faces:

= 33 * 4

= 132 in.²

Surface Area of the whole pyramid:

= 132 + 36

= 168 in.²

[tex]\rule[225]{225}{2}[/tex]

Hope this helped!

Answer:

SA = 168 in.²

Step-by-step explanation:

The surface area is the sum of the area of the base and the areas of the 4 congruent triangular sides.

s = side of the base

h = height of each side

SA = s² + 4(sh/2)

SA = (6 in.)² + 4(6 in.)(11 in.)/2

SA = 36 in.² + 132 in.²

SA = 168 in.²

Answer:

3/4 is the answer.

Answer:

1 hour and 38 minutes

or 98 minutes

Step-by-step explanation:

subtract

4:31-3:31=98 minutes

98-60=38 minutes

= 1 hour and 38 minutes

or

+98 minutes