PLease answer correctly

Convert 50 miles per hour to feet per second ( 1 mile = 5280 feet and 1 hour = 3600 seconds )

wolverine [178]

Answer:

73.3

Step-by-step explanation:

50mi/h * 5280ft/mi * 1h/3600s = 220/3 = 73.3 ft/s

6 0

3 years ago

Read 2 more answers

Solve y - 3x = 13 for y<br><br> y = ?

vampirchik [111]

Answer:

y = 3x + 13

Step-by-step explanation:

Here, we want to solve for y

To solve for y, we simply are going to make y the subject of the formula

We have this as;

y - 3x = 13

y = 13 + 3x

3 0

3 years ago

A study was conducted to measure the effectiveness of hypnotism in reducing pain. The measurements are centimeters on a pain sca

saul85 [17]

Answer:

The 95% confidence interval for the difference would be given by (-1.776;0.376)

We are 95% confidence that the true mean difference is between $-1.776 \leq \mu_d \leq 0.376$ . Since the confidence interval contains the value 0, we don't have enough evidence to conclude that hypnotism appear to be effective in reducing pain.

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".

Let put some notation

x=test value before , y = test value after

x: 6.4 2.6 7.7 10.5 11.7 5.8 4.3 2.8

y: 6.7 2.4 7.4 8.1 8.6 6.4 3.9 2.7

The differences defined as $d_i = y_i -x_i$ and we got:

d: 0.3, -0.2, -0.3, -2.4, -3.1, 0.6, -0.4, -0.1

We can calculate the mean and the deviation for the sample with the following formulas:

$\bar d=\frac{\sum_{i=1}^n d_i}{n}$

$s_d =\frac{\sum_{i=1}^n (d_i -\bar d)^2}{n-1}$

$\bar d=-0.7$ represent the sample mean for the difference

$\mu_d$ population mean (variable of interest)

$s_d$ =1.32 represent the sample standard deviation

n=8 represent the sample size

Confidence interval

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

$\bar d \pm t_{\alpha/2} *\frac{s_d}{\sqrt{n}}$ (1)

In order to calculate the critical value t we need to find first the degrees of freedom, given by:

$df=n-1=8-1=7$

Since the Confidence is 0.95 or 95%, the value of alpha=0.05 and \alpha/2 =0.025, and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.025,8)".And we see that $t_(\alpha/2)=2.306$

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

$-0.7-2.306\frac{1.32}{\sqrt{8}}=-1.776$

$-0.7+2.306\frac{1.32}{\sqrt{8}}=0.376$

So on this case the 95% confidence interval for the difference would be given by (-1.776;0.376)

We are 95% confidence that the true mean difference is between $-1.776 \leq \mu_d \leq 0.376$ . Since the confidence interval contains the value 0, we don't have enough evidence to conclude that hypnotism appear to be effective in reducing pain.

6 0

3 years ago

A cylinder has a base radius of 4m and a height of 6m. What is its volume in cubic m, to the nearest tenths place?

Ronch [10]

<h3>Answer:</h3>

301.6 cubic meters

<h3>Step-by-step explanation:</h3>

A cylinder is a shape with straight sides with circular or oval cross-sections. We know that the cylinder in the question must be a circular cylinder due to its radius description.

Volume Formula

A circular cylinder has a volume of $V=\pi r^2h$ . In this equation, V is the volume, r is the radius, and h is the height. The question tells us that r=4m and h=6m. So, we can plug these values into the formula.