A researcher performed an experiment with two groups. She found the difference of the means for each group. Then she combined the groups, chose two new groups, and found the difference between the means of those new groups. She repeated this process 200 times. The normal distribution of the difference in the means she found is given below. How great would the difference in means between the first two groups have to be in order to considered significant? -At least 7 -At least 8 -At least 9 -At least 10

Answer:

21

Step-by-step explanation:

Answer:

We conclude that the true average lifetime is smaller than what is advertised.

Step-by-step explanation:

The complete question is: Light bulbs of a certain type are advertised as having an average lifetime of 800 hours. The price of these bulbs is very favorable, so a potential customer has decided to go ahead with a purchase arrangement unless it can be conclusively demonstrated that the true average lifetime is smaller than what is advertised. A random sample of 21 bulbs was selected, the lifetime of each bulb determined, and the appropriate hypotheses were tested using SPSS, resulting in the accompanying output.  

                         Sample Mean                         Sample Standard Deviation  

Lifetime               738.44                                                   38.30  

Test the appropriate hypothesis for this study (i.e., state the hypotheses, compute the test statistics, compute the p-value, and make a conclusion). What conclusion  would be appropriate for a significance level of 0.05?

We are given that Light bulbs of a certain type are advertised as having an average lifetime of 800 hours.

A potential customer has decided to go ahead with a purchase arrangement unless it can be conclusively demonstrated that the true average lifetime is smaller than what is advertised.

Let [tex]\mu[/tex] = true average lifetime of the light bulbs.

So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu \geq[/tex] 800 hours    {means that the true average lifetime is greater than or equal to what is advertised}

Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu[/tex] < 800 hours    {means that the true average lifetime is smaller than what is advertised}

The test statistics that will be used here is One-sample t-test statistics because we don't know about the population standard deviation;

                               T.S.  =  [tex]\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }[/tex]  ~   [tex]t_n_-_1[/tex]

where, [tex]\bar X[/tex] = sample mean lifetime = 738.44 hours

             s = sample standard deviation = 38.30 hours

            n = sample of bulbs = 21

So, the test statistics =  [tex]\frac{738.44-800}{\frac{38.30}{\sqrt{21} } }[/tex]  ~  [tex]t_2_0[/tex]

                                     =  -7.36    

The value of t-test statistics is -7.36.

Also, the P-value of test-statistics is given by;

                 P-value = P([tex]t_2_0[/tex] < -7.36) = Less than 0.05% {from t-table}

Since the P-value of our test statistics is less than the level of significance of 0.05, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region.

Therefore, we conclude that the true average lifetime is smaller than what is advertised.

Answer:

-√6    -0.95    √32/8      4/5    2.9    √9

Step-by-step explanation:

4/5, √9, -0.95, √32/8, 2.9, - √6

4/5 = 0.8

√9 = 3

√32/8 = 4√2 / 8 = √2/2 = 0.707

-√6 = -2.449

-√6    -0.95    √32/8      4/5    2.9    √9

Answer:

C

Step-by-step explanation:

6x=36

6x/6 cross out

36/6=6

×=6

so the answer is C

We just need to divide so we can find the base length of the triangle:

207 / 18 = 11.5

Therefore, the base length of the triangle is 11.5 inches.

Best of Luck!

Answer:

23 inches

Step-by-step explanation:

A = [tex]\frac{1}{2}[/tex] bh

207 = [tex]\frac{1}{2}[/tex] b x 18

[tex]\frac{207}{9}[/tex] = b

b = 23

Answer:

14 and 16

Step-by-step explanation:

Consecutive even numbers are even numbers that follow each other from smallest to biggest for example 2,4,6,8 are consecutive even numbers. So the consecutive even numbers that have a sum of 30 are 14 and 16 (14+16=30).

HOPE IT HELPED

Answer:

Step-by-step explanation:

y - 5 = -2(x - 1)

y - 5 = -2x + 2

y = -2x + 7

Option 1 is the answer

Answer:

The answer is not an inverse function.

Step-by-step explanation:

The inverse function does not reverse. In other words,  f(x) = x-5/10 and h(x) =10x+5 does not mirror.

Answer:

207

Step-by-step explanation:

[tex]w^{2}[/tex]=9, but since there is a negative sign, it will be negative 9.

-11(uv) is -11(-8), and that equals 88.

2[tex]v^{2}[/tex] is 2(64), which equals 128.

-9+88+128 is 207.

Hope that helps!

Answer:

The answer is 264

Step-by-step explanation:

We start with a ratio of inches to miles-        6:12

we see that it can be simplified to                  1:2

if we see that on the map it is 22in,             22:?

we got 1 to 22 by multiplying 1*22=22

do the same to the 12: 12*22=264

Answer:

its c. <vwx

Step-by-step explanation:

i got it right

Answer:

a) s=4A

Step-by-step explanation:

If you read the equation out loud it may help!

Sam=4 times Allie

Sams age Equals 4 times the age of Allie

Answer:  Big number

Step-by-step explanation:

In division, does the big or small letter go first?

Answer:

In division, the big one go first.

Step-by-step explanation:

So, when you do division, you can put the big or small ones first but, preferably the big ones because it will be easier to solve the equation.

Answer: 5/9 is ur answer

Step-by-step explanation:

Answer: 5/9

Step-by-step explanation:

5÷9 is 0.555 repeating (which is why there is a line at the top of the 5).

Answer:

-2

Step-by-step explanation:

Point A = 1

Point B = - 5

Midpoint :

Step-by-step explanation:

If ∠1 and ∠2 are supplementary, then m∠1 + m∠2 = 180° (1).

If ∠2 and ∠3 are supplementary, then m∠2 + m∠3 = 180° (2).

From (1) we have

m∠1 + m∠2 = 180°           /subtract m∠1 from both sides

m∠2 = 180° - m∠1

substitute it to (2)

(180° - m∠1) + m∠3 = 180°

180° - m∠1 + m∠3 = 180°     /subtract 180° from both sides

- m∠1 + m∠3 = 0        /add m∠1 to both sides

m∠3 = m∠1 ⇒ m∠1 = m∠3 ⇒ ∠1 ≅ ∠3

Answer:

8

Step-by-step explanation:

[tex]\frac{2}{5} (1+24) + \frac{1}{2} (2-6)[/tex]=

[tex]\frac{2}{5} (25)+ \frac{1}{2} (-4)[/tex]=

[tex]10-2=8[/tex]

Answer:

868.065

Step-by-step explanation:

198.040 ÷ 98.1 + 100 x 4.3

= 2.0188 + 100 x 4.3

= 201.8756 x 4.3

= 868.065

Steps to solve:

198.040 ÷ 98.1

~Divide

2.0187563... or 2.02

Steps to solve:

100 * 4.3

~Multiply

430

Best of Luck!

Answer:

[tex] \boxed{ \bold{ \huge{ \boxed{ \sf{ \sqrt{58} \: \: units}}}}}[/tex]

Step-by-step explanation:

Let the points be A and B

Let A ( 3 , -2 ) be ( x₁ , y₁ ) and B ( -4 , 1 ) be ( x₂ , y₂ )

Finding the distance between these points

[tex] \boxed{ \sf{distance = \sqrt{ {(x2 - x1)}^{2} + {(y2 - y1)}^{2} } }}[/tex]

[tex] \dashrightarrow{ \sf{ \sqrt{ {( - 4 - 3)}^{2} + {(1 - ( - 2))}^{2} } }}[/tex]

[tex] \dashrightarrow{ \sf{ \sqrt{ {( - 4 - 3)}^{2} + {(1 + 2)}^{2} } }}[/tex]

[tex] \dashrightarrow{ \sf{ \sqrt{ {( - 7)}^{2} + {(3)}^{2} } }}[/tex]

[tex] \dashrightarrow{ \sf{ \sqrt{49 + 9}}} [/tex]

[tex] \dashrightarrow{ \sf{ \sqrt{58} }}[/tex] units

Hope I helped!

Best regards! :D

Hey there! I'm happy to help!

To get 5/6 to 1, you multiply by 6/5. This means that to see your mph, you multiply 85 by 6/5!

85(6/5)=102

The speed is 102 mph.

Have a wonderful day! :D

Answer: assuming you mean divide 4mil by 21, the answer is 204365.619

Step-by-step explanation:

Answer:

4.9x10⁻⁶

Step-by-step explanation:

21 / 4291678 = 4.9x10⁻⁶

Answer:

(x, y, z) → (18, 22, 9)

Step-by-step explanation:

sum of three numbers is 49

x + y + z = 49

second number is 5 less than three times the third number

y = 3z - 5

first number is twice amount of third number

x = 2z

set of equations

x + y + z = 49

y = 3z - 5

x = 2z

plug in 2nd and 3rd equation into first

(2z) + (3z - 5) + z = 49

combine like terms

2z + 3z - 5 + z = 49

6z - 5 = 49

add 5 to both sides

6z = 54

divide by 6

z = 9

plug z into 2nd and 3rd equations

y = 3(9) - 5

y = 27 - 5

y = 22

x = 2(9)

x = 18

check:

18 + 22 + 9 = 49

(x, y, z) → (18, 22, 9)

Answer:

2.970600004839 × 10^5

Step-by-step explanation:

First, we add up these 2 numbers.

297,060 + 0.0004839 = 297060.0004839

Then, we convert that into scientific notation.

297060.0004839 = 2.970600004839 × 10^5

Finally, we check if it's right.

10^5 = 100000

2.970600004839 * 100000 = 297060.0004839

Hope this helps.

Answer:

B. the product of two irrational numbers

Step-by-step explanation:

To be a rational number, we need to multiply two irrational numbers

An example would be

sqrt(2) * sqrt(2) = sqrt(4) = 2

Answer:

The product of two irrational numbers

Step-by-step explanation:

Answer:

The best conclusion that can be made based on the data on the dot plot is:

The mean difference is not significant because the re-randomization show that it is within the range of what could happen by chance.

Step-by-step explanation:

Randomization is the standard used to compare the observational study and balance the factors between the treatment groups and eliminate the variables' influence. Some studies analyze that the treatment in the randomization calculates the appropriate number of the subjects as the treatment to memorize is 8.9, and the treatment for the B is 12.1 words.

The mean difference is not significant because the re-randomization shows that it is within the range of what could happen by chance.

The treatment group using technique A reported a mean of 8.9 words.

The treatment group using technique B reported a mean of 12.1 words.

After the data are re-randomized, the differences of means are shown in the dot plot.

The result is significant because the re-randomization show that it is outside the range. The best conclusion that can be made based on the data on the dot plot is:

The mean difference is not significant because the re-randomization show that it is within the range of what could happen by chance.

Answer:

The answer is actually

-The difference of the means is significant because the re-randomizations show that it is outside the range of what could happen by chance.

*just took the test hope this helps:)*

Answer:

It belongs to the... RATIONAL number set

Answer:

C and D is correct

Step-by-step explanation:

C: Debit is negative, and if you add 27 to -14, you get 13 which is Maria's account.

D: Its the same thing but opposite. 13 minus 27 is -14.

♡ Hope it helps ♡

Answer:

both c and d

Step-by-step explanatioin

nobody is answering my question so im saving up like 100 points so someone will actually do it so ye

Answer:

the answer is y=-5