91/2 gallons =? quarts

g A researcher wants to construct a 95% confidence interval for the proportion of children aged 8-10 living in Atlanta who own a

Helga [31]

Answer:

The sample size needed is 2401.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $1-\alpha$ , we have the following confidence interval of proportions.

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

The margin of error of the interval is:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

95% confidence level

So $\alpha = 0.05$ , z is the value of Z that has a pvalue of $1 - \frac{0.05}{2} = 0.975$ , so $Z = 1.96$ .

Estimate the sample size needed if no estimate of p is available so that the confidence interval will have a margin of error of 0.02.

We have to find n, for which M = 0.02.

There is no estimate of p available, so we use $\pi = 0.5$

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

$0.02 = 1.96\sqrt{\frac{0.5*0.5}{n}}$

$0.02\sqrt{n} = 1.96*0.5$

$\sqrt{n} = \frac{1.96*0.5}{0.02}$

$(\sqrt{n})^{2} = (\frac{1.96*0.5}{0.02})^{2}$

$n = 2401$

The sample size needed is 2401.

7 0

3 years ago

Read 2 more answers

Find an equivalent ratio in simplest terms:<br> 12 : 32

jarptica [38.1K]

Answer:

3:8 i think

Step-by-step explanation:

5 0

2 years ago

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Lena is 10 years old. She asks her dad how old he is. He tells her that the lowest common multiple of their ages is 14 times the

Ksju [112]

Answer:

35

Step-by-step explanation:

We know the factors of Lena's age are 2 and 5. The least common multiple must have these factors and the factors of 14, so will at least have factors of 2, 5, and 7.

Apparently, the dad's age is 5·7 = 35.

___

The GCF is 5; the LCM is 70 = 5×14.

_____

Sometimes, I use a little 3-part diagram to think about LCM and GCF. Here, it would look like ...

(2 [5) 7]

where the numbers in curved brackets (2·5) and the numbers in square brackets [5·7] are factors of the two numbers of concern (Lena's age, her dad's age). The middle number in both brackets [5) is the greatest common factor, and the product of all three numbers is their least common multiple.

Here, the product of outside numbers, 2·7 = 14, represents the ratio of the LCM to the GCF. We know that Lena's age has factors of only 2 and 5, so the numbers in the diagram have to be (2[5)7], where 2 and 7 are on the ends and 5 is in the middle.

7 0

3 years ago

Which graph shows a negative rate of change for the interval 0 to 2 on the x-axis?

777dan777 [17]

Answer:

THE ANSWER OM EDGE IS (C)

UR WELCOME

Step-by-step explanation:

have a great day :)

7 0

3 years ago

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Jim needs to divide 762 coupon books equally among 9 stores. In which place is the first digit of the quotient? Select the word

nevsk [136]

Answer:

ones

Step-by-step explanation:

It is given that Jim wants to divide 762 coupons equally among 9 stores.

So dividing 762 by 9, we get

$=\frac{762}{9}$

= 84.66

The position of the digit before the decimal place start with 'ones' and then proceeds to tens, hundreds, thousands, etc.

Therefore, the first digit of the quotient is in the ones place of the position value or place value.

6 0

2 years ago