The equation for the circle below is x squared+ y squared= 100. what is the length of the circles radius

ss7ja [257]

Answer:

it can either be written as x > -1 and x < 2 or as -1 < x < 2.

Step-by-step explanation:

The graph of a compound inequality with an "and" represents the intersection of the graph of the inequalities. A number is a solution to the compound inequality if the number is a solution to both inequalities. It can either be written as x > -1 and x < 2 or as -1 < x < 2.

6 0

3 years ago

Bob Nale is the owner of Nale’s Quick Fill. Bob would like to estimate the mean number of gallons of gasoline sold to his custom

ira [324]

Answer:

a) The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

b) The 99% confidence interval would be given by (4.969;6.431)

c) We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

Step-by-step explanation:

1) 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".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=1.9$ represent the population standard deviation

n=45 represent the sample size

2) Part a

The best estimator for the population mean is given by the sample mean $\hat \mu = \bar X = 5.70$

3) Part b. Develop a 99 percent confidence interval for the population mean.

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

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.95 or 95%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$

Now we have everything in order to replace into formula (1):

$5.7-2.58\frac{1.9}{\sqrt{45}}=4.969$

$5.7+2.58\frac{1.9}{\sqrt{45}}=6.431$

So on this case the 99% confidence interval would be given by (4.969;6.431)

4) Part c. Interpret the meaning of part (b).

On this case we can say this: We are 99% confident that the true mean for th number of gallons of gasoline sold to his customers is between 4.969 and 6.431.

4 0

3 years ago

The top of a mountain is 2,450 feet above sea level a shipwreck was discover 310 feet below sea level what is the distance betwe

arlik [135]

Answer:

$d=2,760\ ft$