1 3/4d= 14 what is the value of d

A group of 59 randomly selected students have a mean score of 29.5 with a standard

algol [13]

Answer:

$29.5-1.671\frac{5.2}{\sqrt{59}}=28.37$

$29.5+1.671\frac{5.2}{\sqrt{59}}=30.63$

And we can conclude that the true mean for the scores are given by this interval (28.37; 30.63) at 90% of confidence

Step-by-step explanation:

Information given

$\bar X = 29.5$ represent the sample mean

$\mu$ population mean

s= 5.2 represent the sample standard deviation

n=59 represent the sample size

Confidence interval

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

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

The degrees of freedom are given by:

$df=n-1=59-1=58$

The Confidence interval is 0.90 or 90%, the significance is $\alpha=0.1$ and $\alpha/2 =0.05$ , and the critical value is $t_{\alpha/2}=1.671$

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

$29.5-1.671\frac{5.2}{\sqrt{59}}=28.37$

$29.5+1.671\frac{5.2}{\sqrt{59}}=30.63$

And we can conclude that the true mean for the scores are given by this interval (28.37; 30.63) at 90% of confidence

8 0

2 years ago

Brittney made a proportional copy of a figure by multiplying each side length by 1/4. Drag numbers to complete the table

bonufazy [111]

Answer:

Step-by-step explanation:

Side Original length Copy length $\frac{Original length}{Copy length}$

a 4 1 $\frac{4}{1}=4$

b 6 1.5 $\frac{6}{1.5}=4$

c 20 5 $\frac{20}{5}=4$

d 16 4 $\frac{16}{4}=4$

4 0

3 years ago

Read 2 more answers

What is the equation of the line that is parallel to the line 2x+3y=-8 and passes through the point (2,-2)?

Leya [2.2K]

Equation of line passing through (2, -2) and parallel to 2x+3y = -8 is $y=\frac{-2 x}{3}+\frac{-2}{3}$

<h3><u>Solution:</u></h3>

Need to write equation of line parallel to 2x+3y=-8 and passes through the point (2, -2)

Generic slope intercept form of a line is given by y = mx + c

where "m" = slope of the line and "c" is the y - intercept

Let’s first find slope intercept form of 2x+3y=-8 to get slope of line

$\begin{array}{l}{2 x+3 y=-8} \\\\ {=>y=\frac{-2 x-8}{3}} \\\\ {\Rightarrow y=-\frac{2}{3} x-\frac{8}{3}}\end{array}$

On comparing above slope intercept form of given equation with generic slope intercept form y = mx + c,

$\text {for line } 2 x+3 y=-8, \text { slope } m=-\frac{2}{3}$

We know that slopes of parallel lines are always equal

So the slope of line passing through (2, -2) is also $m=-\frac{2}{3}$

Equation of line passing through $(x_1 , y_1)$ and having slope of m is given by

$\left(y-y_{1}\right)=\mathrm{m}\left(x-x_{1}\right)$

$\text { In our case } x_{1}=2 \text { and } y_{1}=-2$

Substituting the values in equation of line we get

$(y-(-2))=-\frac{2}{3}(x-2)$

$\begin{array}{l}{\Rightarrow y+2=\frac{-2 x+4}{3}} \\\\ {=>3(y+2)=-2 x+4} \\\\ {=>3 y+6=-2 x+4} \\\\ {3 y=-2 x-2}\end{array}$

$y=\frac{-2 x}{3}+\frac{-2}{3}$

Hence equation of line passing through (2 , -2) and parallel to 2x + 3y = -8 is given as $y=\frac{-2 x}{3}+\frac{-2}{3}$

7 0

3 years ago

What is 8.1 divided by ( -0.9 ) ?

Ksju [112]

-9 hopefully this helps

8 0

2 years ago

Read 2 more answers

An electronics company makes communication devices for military contracts. The company just completed two contracts. The navy co

adelina 88 [10]

Answer:

Workers of army contract were more productive.

Step-by-step explanation:

To determine on which contract the workers were more productive compute the work done per hour by the workers for both contracts.

<u>Navy Contract</u>:

Number of devices = 2,300

Number of workers = 25

Number of weeks = 2 weeks

Number of hours per week = 40

The number of hours it took 25 workers to produce 2300 devices is =

$=25\times2\times40\\=2000\ hours$

Then number of devices produced in 1 hour is = $\frac{2300}{2000}= 1.15\ devices\ per\ hour$

<u>Army Contract</u>:

Number of devices = 5,500

Number of workers = 35

Number of weeks = 3 weeks

Number of hours per week = 40

The number of hours it took 35 workers to produce 5500 devices is = $=35\times3\times40\\=4200\ hours$

Then number of devices produced in 1 hour is = $\frac{5500}{4200}= 1.31\ devices\ per\ hour$

The workers for the army contract are more productive since they produce 1.31 devices per hour whereas the workers for navy contract produces 1.15 devices per hour.

4 0

2 years ago