A usability test was conducted to evaluate the design of a store website. The times to complete a certain task were recorded for a sample of 48 users. The sample mean time was 70 seconds with a 95% margin of error of 10 seconds. In other words, researchers estimated with 95% confidence that the mean time to complete the task was between 60 and 80 seconds for all website users. Only one of the following statements is true. Select the correct statement.
1. the probability that the mean time μ will fall between 60 and 80 is 0.95.
2. If many samples are collected from the same population, about 95% of the samples will produce confidence intervals that contain the population mean μ.
3. If a second sample from the same population is selected and a 95% confidence interval is constructed, the new confidence interval will be the same as the 95% C.I. defined in the first study.
4. If the study is repeated, and a new 95% confidence interval is computed, there is 95% chance that the new interval contains the sample mean value >= 40 seconds.

Answer:

The 96% confidence interval estimate for the mean daily number of minutes that BYU students spend on their phones in fall 2019 is between 306.65 minutes and 317.35 minutes.

Step-by-step explanation:

Confidence interval normal

We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:

[tex]\alpha = \frac{1 - 0.96}{2} = 0.02[/tex]

Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].

That is z with a pvalue of [tex]1 - 0.02 = 0.98[/tex], so Z = 2.054.

Now, find the margin of error M as such

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.

[tex]M = 2.054\frac{54}{\sqrt{430}} = 5.35[/tex]

The lower end of the interval is the sample mean subtracted by M. So it is 312 - 5.35 = 306.65 minutes

The upper end of the interval is the sample mean added to M. So it is 312 + 5.35 = 317.35 minutes

The 96% confidence interval estimate for the mean daily number of minutes that BYU students spend on their phones in fall 2019 is between 306.65 minutes and 317.35 minutes.

Step-by-step explanation:

given

3n + 2 + 5 = 4

3n + 7 = 4

3n = 4 - 7

3n = - 3

n = - 3 / 3

n = -1

Hope it will help :)❤

Answer:

choice 2) 1/5 x 3/15 = 3/75 = 1/25

Step-by-step explanation:

Answer:

EX :A jar contains 10 red marbles, 4 white marbles, and 2 blue marbles. Two ... To solve this question, you can solve for the probability of choosing 2 marbles that are pink and ... There are two even numbers and three odd numbers, so P (even) = 2/5 and P (odd) = 3/5. ... In a bag, there are 10 red, 15 green, and 12 blue marbles.

Step-by-step explanation:

Answer:

8 {m},{a},{t},{m,a},{m,t},{a,t},{m,a,t},{}

I'm sorry m8 the only options I can give you is life or death. also can u give me brainliest many thank xoxo

Answer:

3: 2 because for every 4 men there was 1 women so 4 + 1 = 5 and x 2 = 10 so thats the number of adults and since we multiplied by 2 we have to women

Answer:

1748

Step-by-step explanation:

Tuesday + Wednesday - Monday

This is false, we can prove this with a simple counterexample.

2^2=4

4 is divisible by 4

but 2 is not divisible by 4

Answer:

a. 30 m

I hope it helps....

Answer:

30m

Step-by-step explanation:

[tex]18m^{2}[/tex]/m + 4m(3)

= [tex]30m^{2}[/tex]/m

= 30m

Hope it helps,

Please mark me as the brainliest

Thank you

Answer:

There is a error that is

Not : 4 × 6

Correct: 4 × 4

Step-by-step explanation:

Given ,

Base of the parallelogram = 4 in.

Height of the parallelogram = 4 in.

Therefore,

Area of the parallelogram = base × height

= 4 in. × 4 in.

[tex] = 16 {in.}^{2} (ans)[/tex]

This question is incomplete, the missing table is uploaded along this answer below.

Answer:

percentage of age reduction is 40

Option B) 40% is the correct answer

Step-by-step explanation:

Given the data in the question;

from the table in the image below;

sample x = 25.69 , 25.58 , 24.78 , 24.94 , 24.87 , 24.63 , 25.70 , 25.52 , 24.95 , 24.91

mean = ∑x/n

where n is sample size

= (25.69  + 25.58  +24.78  + 24.94  + 24.87  + 24.63  + 25.70  + 25.52  +24.95 ) / 10

= 251.57 / 10

mean u = 25.157

so;

S/N    Sample (X)       Mean (u)       (X-U)²

1            25.69              25.157      0.284089

2           25.58              25.157      0.178929

3           24.78              25.157       0.142129

4           24.94              25.157       0.047089

5           24.87              25.157       0.082369

6           24.63              25.157       0.277729

7           25.7                 25.157       0.294849

8           25.52              25.157       0.131769

9           24.95              25.157        0.042849

10          24.91               25.157       0.061009

Total     251.57                               1.54281

Mean  25.157

Sample Variance = ∑(x-u)²/n-1 = 1.54281 / (10 - 1) = 1.54281 / 9 = 0.1714

Standard deviation STD1 = √ (variance) = √0.1714 = 0.414

now, for 6-sigma capability, Cpk = 2

Cpk = min of ( USL - mean ) / 3×STD), (Mean - LSL) / 3×STD

since our mean is centered between USL and LSL;

Cpk = ( 26.5 - 25 ) / 3×STD2

we substitute

2 = ( 26.5 - 25 ) / 3×STD2

6STD2 = 1.5

STD2 =  1.5 / 6

STD2 = 0.25

so current standard deviation STD1 = 0.414

required standard deviation for 6-sigma process STD2 = 0.25

so percentage of age reduction will be;

⇒ ( 0.414 - 0.25 ) 0.414 = 0.164 / 0.414 = 0.396 ≈ 0.4

⇒ 0.4 × 100 = 40%

Therefore, percentage of age reduction is 40

Option B) 40% is the correct answer

Answer:

Ikr

Step-by-step explanation:

I used to be able to know what 1 + 1 but now I have no idea how to solve that

(Im jk btw lol)

Answer:

To find the area of a composite figure, separate the figure into simpler shapes whose area can be found. Then add the areas together. Be sure than none of the simpler figures have overlapping areas. To calculate the area of a composite shape you must divide the shape into rectangles, triangles or other shapes you can find the area of and then add the areas back together. To find the area of a rectangle, multiply its height by its width. For a square you only need to find the length of one of the sides (as each side is the same length) and then multiply this by itself to find the area. This is the same as saying length2 or length squared.

Answer:

0.087 = 8.7% probability that this person made a day visit.

0.652 = 65.2% probability that this person made a one-night visit.

0.261 = 26.1% probability that this person made a two-night visit.

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)}[/tex]

In which

P(B|A) is the probability of event B happening, given that A happened.

[tex]P(A \cap B)[/tex] is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: Made a purchase.

Probability of making a purchase:

10% of 20%(day visit)

30% of 50%(one night)

20% of 30%(two night).

So

[tex]p = 0.1*0.2 + 0.3*0.5 + 0.2*0.3 = 0.23[/tex]

How likely is it that this person made a day visit?

Here event B is a day visit.

10% of 20% is the percentage of purchases and day visit. So

[tex]P(A \cap B) = 0.1*0.2 = 0.02[/tex]

So

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.02}{0.23} = 0.087[/tex]

0.087 = 8.7% probability that this person made a day visit.

A one-night visit?

Event B is a one night visit.

The percentage of both(one night visit and purchase) is 30% of 50%. So

[tex]P(A \cap B) = 0.3*0.5 = 0.15[/tex]

So

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.15}{0.23} = 0.652[/tex]

0.652 = 65.2% probability that this person made a one-night visit.

A two-night visit?

Event B is a two night visit.

The percentage of both(two night visit and purchase) is 20% of 30%. So

[tex]P(A \cap B) = 0.2*0.3 = 0.06[/tex]

Then

[tex]P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.06}{0.23} = 0.261[/tex]

0.261 = 26.1% probability that this person made a two-night visit.

Answer:

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

Step-by-step explanation:

Equation of a line:

The equation of a line has the following format:

[tex]y = mx + b[/tex]

In which m is the slope and b is the y-intercept(value of y when x = 0).

If two lines are perpendicular, the multiplication of their slopes is -1.

Contains (0, 2)

This means that [tex]b = 2[/tex]. So

[tex]y = mx + 2[/tex]

Finding the slope:

Perpendicular to y = 2/3x + 1 means that:

[tex]\frac{2m}{3} = -1[/tex]

[tex]2m = -3[/tex]

[tex]m = -\frac{3}{2}[/tex]

So

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

Answer:

I think is the 3rd one but I am not sure

Answer:

Carlotta needs 24 orange beads for her necklace.

Step-by-step explanation:

For each necklace, the ratio of blue beads to orange beads is 3 to 2. or 3:2

Total beads given to make a necklace is = 60

Let the number of orange beads be = x

The ratio is 2 orange beads out of 5 total beads

So, we can represent the ratio as:

x=24

Hence, Carlotta needs 24 orange beads for her necklace.

Blue beads needed =  

We can also check the ratio for blue beads to orange beads:

Divide by 4, we get

Divide by 3, we get

 ...... (the given ratio)

Therefore, Carlotta needs 24 orange beads for her necklace

Answer:

1 2 = 2 4 = 3 6 = 4 8 = etc. All of these fractions are located at the same point on the number line. Therefore, they represent the same number. From the paper folding exercises, we see that increasing both numerator and denominator of a fraction by the same factor gives an equivalent or equal fraction.

Hope this helps :) Just know I tried.

Answer:

4/3

10/3

24/3

...........

Answer:

4/3

10/3

24/3 or 8

Step-by-step explanation:

x = y - 2/3

2 - 2/3 = 2/1 - 2/3 = 6/3 - 2/3 = 4/3

y = x + 2/3

8/3 + 2/3 = 10/3

y = x + 2/3

22/3 + 2/3 = 24/3 = 8

Answer:

23

Step-by-step explanation:

Answer:

Step-by-step explanation:

m = 60-y

m+5 = 65-y

Answer:

183.6

Step-by-step explanation:

170, percentage increased by 8% (percent) of its value = 183.6

Answer:

183.6

Step-by-step explanation:

170 divided by 100 = 1.7 multiplied by 8 = 13.6 + 170 = 183.6

Answer:

No conozco este pero puedo ayudarte con otros

Step-by-step explanation:

Based on the table given, the bookstore that discounts more pesos from the original price is Leer es saber.

Discount from El cuentacuentos:

= 100 x 20%

= $20

Discount from Leer es saber:

= 125 x 25%

= $31.25

Discount from El librote:

= 80 x 5%

= $4.00

Discount from Imagina:

= 90 x 10%

= $9

The highest is therefore Leer es saber.

The rest of the question is:

Qué librería descuenta más pesos del precio original?

Find out more on discounts at https://brainly.com/question/1548141.

#SPJ6

The balance at the end of one years is; $502.5. The equation that that represents the balance in the account is $500 x (1.005)^1

The amount of money in the bank account would grow at an exponential rate. then the formula for calculating future value:

FV = P (1 + r)^nm

Where:

FV = Future value

P = Present value

R = interest rate

N = number of years

We are given that bank account pays 0.5% monthly interest. If $500 is put in the account, it will the balance be at the end of one year,

$500 x (1 + 0.5/100)^1

$500 x (1.005)^1

= $502.5

To learn more about future value, please check: brainly.com/question/18760477

#SPJ1

Answer: $530.84

Step-by-step explanation: The principal is $500 with 0.5% added MONTHLY. One year has 12 months so we must calculate the interest for 12 months.

$500(1.005)^12 = $530.838 which rounds to $530.84

Answer:

he spent $34.67 that is the answer

you would spend $30

Step-by-step explanation:

if 20 calculator cost 120 then you would divide 20 by 120 which would give you 6 dollars per calculator then you would multiply that by 5 which would give you a $30 for five calculators.

Answer:

where is the table?

I am just telling you how to get the cost of 5 calculators...

Step-by-step explanation:

Cost of 20 cal.=$120

Cost of 1 cal.=120/20

So,

cost of 5 calculators=

120/20*5

=$30

Hope it helps you