What is two-fifths of three-sevenths?

steposvetlana [31]

Answer:

17 units

Step-by-step explanation:

You can find the lenght of drawing a triangle and counting the x units and y units, thereby the AB would be the hypotenuse.

X units ( base ) = 15 units

Y units ( height ) = 8 units

AB = root of 8^2 + 15^2

AB = root of 289

AB = 17 units

Hope it helps :)

Mark it as brainliest answer pls :)

5 0

3 years ago

What’s the answer to this

Andrews [41]

Answer:

A point on either side of the line

Step-by-step explanation:

To determine which side to shade, you look at a point on each side of the line. One will make the inequality true and one will not. Shade on the side that will make the inequality true

8 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

What are the steps to find the slope of the line through the pair of points ? <br>

Artyom0805 [142]

Answer:

$\frac{-15}{-14} \\$

Step-by-step explanation:

You would do y2-y1 over x2-x1. In your equation, this would be -15-0 over -11-3, giving you -15 over -14

8 0

3 years ago

Awesome Car company sold 20 cars this week.their goal is to sell at least 25% more next week. Write an inequality that represent

Serga [27]

Twenty-five percent (25%) of 20 is equal to 5. Therefore, the company is planning or targeting to sell at least 25 cars next week. We let the number of cars be x. The inequality that best represent the scenario above is,
x ≥ 25

6 0

3 years ago

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