The name of the compound kf is..... a. sodium chloride b. potassium fluoride

The radius of a circle is 15 inches. What is the circumference of the circle? Write your answer using .

dem82 [27]

Answer: C ≈ 94.25 in

Step-by-step explanation:

4 0

2 years ago

3. Using the sample size of 800 and the proportion 0.47, calculate the margin of error associated with the estimate of the propo

salantis [7]

Answer:

$ME=1.96\sqrt{\frac{0.47 (1-0.47)}{800}}=0.0346$

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

Solution to the problem

We assume for this case a confidence level of 95%. In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by $\alpha=1-0.95=0.05$ and $\alpha/2 =0.025$ . And the critical value would be given by:

$z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96$

The confidence interval for the mean is given by the following formula:

$\hat p \pm z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$

The margin of error for the proportion interval is given by this formula:

$ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$ (a)

And if we replace the values obtained we got this:

$ME=1.96\sqrt{\frac{0.47 (1-0.47)}{800}}=0.0346$

6 0

3 years ago

What is 345,973 rounded to the nearest hundred

8090 [49]

345973 rounded to the nearest hundred is 346000

3 0

3 years ago

Evaluate the expression. 7.4+6 - 12:4 Plz help me

juin [17]

Answer:

7 . 4 + 6 - 12 : 4 = 31

Step-by-step explanation:

* To solve this problem lets revise the order of operations in

mathematics

- The operations are:

# Addition

# Subtraction

# Multiplication

# Division

# Exponentiation

# Grouping ⇒ Parenthesis or brackets

- The order of these operations is:

# Parenthesis

# Exponents

# Multiplication and Division which comes first from left to right

# Addition and Subtraction which comes first from left to right

- There is a word made from the first letter of each operation

PEMDAS to remember the order of operations

* Lets solve the problem

∵ 7 . 4 + 6 - 12 : 4

∵ The (.) means multiply the numbers

∵ The symbol (:) means divided the numbers

∴ At first multiply 7 by 4 and divide 12 by 4

∴ (7 × 4) + 6 - (12 ÷ 4)

∴ 28 + 6 - 3

∵ Addition comes before subtraction from the left

∴ (28 + 6) - 3

∴ 34 - 3 = 31

∴ 7 . 4 + 6 - 12 : 4 = 31

4 0

3 years ago

Find the midpoint of the segment joining X(6,5) and Y(9,2). I'm lost geomerty

olasank [31]

Answer:

Is there a graph?

Step-by-step explanation:

3 0

3 years ago