Lindsay is playing a video game.

Plz help!!! Can you have an explanation or if you can't explain just show your work or something!!

inysia [295]

I can not really explain it I just know it. the answer I do believe is 3,000

7 0

3 years ago

If the equation of a line has an undefined slope and passes through the point (1, 3, which form would be used to write the equat

umka21 [38]

Hello :
the line has an undefined slope if paralel a axis- y : equation x = 1 (<span>passes through the point (1, 3))</span>

6 0

4 years ago

What are the focus and directrix of the parabola that is the graph of the function f(x)=x²?

Hitman42 [59]

Answer:

Step-by-step explanation:

Given

$y=x^2$

comparing it with standard equation $x^2=4ay$

so 4a=1

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

so Focus of parabola is (0,0)

directrix

y=-a

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

$y=-\frac{1}{4}$

5 0

4 years ago

A nation has five types of coins: sinds, dalts, lorgs, harps, and plunks.

USPshnik [31]

<h3>Answer: d) plunk</h3>

=================================================

Work Shown:

When comparing units like inches, feet and yards, we need to get everything in the same unit to make a valid comparison. So we'd need to convert everything to inches for instance. The same idea applies to these five coins. We need to get everything in either lorgs, sinds, plunks, harps or dalts (pick one of those five).

It's effectively the same as trying to convert dollars into cents (eg: $1.37 converts to 137 cents). Or you can think of it as 1 dollar = 100 cents, 1 quarter = 25 cents, 1 dime = 10 cents, and so on.

The steps in the various sections below will aim to get all the coins converted to lorgs as our base unit. I found the lorg coin to be the smallest of value through trial and error, which is why I'm aiming to get everything in terms of lorgs.

The four given equations are

1 sind = 4 lorgs
2 plunks = 5 dalts
5 sinds = 2 harps
1 plunk = 3 harps

I'll refer to them as equation (1) through equation (4) in that order above.

--------------

1 sind = 4 logs .... equation (1)

5 sinds = 20 lorgs .... multiply both sides by 5

2 harps = 20 lorgs .... replace "5 sinds" with "2 harps" from equation (3)

1 harp = 10 lorgs .... divide both sides by 2; call this equation (5)

--------------

1 plunk = 3 harps .... equation (4)

1 plunk = 3*(1 harp)

1 plunk = 3*(10 lorgs) .... plug in equation (5)

1 plunk = 30 lorgs .... call this equation (6)

---------------

2 plunks = 5 dalts ..... equation (2)

5 dalts = 2 plunks

5 dalts = 2*(1 plunk)

5 dalts = 2*(30 lorgs) .... replace 1 plunk with 30 lorgs; see equation (6)

5 dalts = 60 lorgs

1 dalt = 12 lorgs ..... divide both sides by 5; call this equation (7)

----------------

We found the following conversions:

1 sind = 4 lorgs .... given as equation (1)
1 dalt = 12 lorgs .... found earlier as equation (7)
1 harp = 10 lorgs .... equation (5)
1 plunk = 30 lorgs .... equation (6)

Each of those equations helps us see how much the value of the coins sind, dalt, harp, plunk are in terms of lorgs.

We can see that 1 plunk yields the most lorgs at 30. So the plunk coin is the most valuable. The lorg coin is least value since you need 4 of those coins to make the second lowest coin of 1 sind.

The order of the coins value from least to greatest is: lorg, sind, harp, dalt, plunk.

5 0

3 years ago

Six measurements were made of the magnesium ion concentration (in parts per million, or ppm) in a city's municipal water supply,

myrzilka [38]

Answer:

$163.83-4.03\frac{20.094}{\sqrt{6}}=130.77$

$163.83+4.03\frac{20.094}{\sqrt{6}}=196.89$

So on this case the 99% confidence interval would be given by (130.77;196.89)

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".

Data: 175 177 175 180 138 138

We can calculate the mean and the deviation from these data with the following formulas:

$\bar X= \frac{\sum_{i=1}^n x_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (x_i -\bar X)^2}{n-1}}$

$\bar X=163.83$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=20.093 represent the sample standard deviation

n=6 represent the sample size

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

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

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=6-1=5$

Since the Confidence is 0.99 or 99%, 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: "=-T.INV(0.005,5)".And we see that $t_{\alpha/2}=4.03$

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

$163.83-4.03\frac{20.094}{\sqrt{6}}=130.77$

$163.83+4.03\frac{20.094}{\sqrt{6}}=196.89$

So on this case the 99% confidence interval would be given by (130.77;196.89)

7 0

3 years ago