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Sorry, I didn't read the question properly.  Maybe someone else can help.

You have found the inverse function anonymous person.  By adding the y= you have assumed that it was supposed to be an equation.  That is fair enough it didn't make sense otherwise.

Thank you for answering - we like everyone to answer questions.  

The data set I have is 14.2, 15.6, 16.3, 17.1, 17.9, 18.6, 20.0

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Let's see how much of statistics I remember!!

First, let's find the mean (average) of this data set. We just sum the numbers and divide by the number of them that we have, (7)........

This gives:   ( 14.2+ 15.6 +16.3 + 17.1 +17.9 + 18.6 + 20.0 ) / 7   = 17.1

The, we subtract each of the values from the mean and square the result....note that we can disregard 17.1 itself !! (Subtracting it from the mean = 0)

So we have

(17.1 - 14.2)² = (2.9)²  = 8.41

(17.1 - 15.6)² = (1.5)²  = 2.25

(17.1 - 16.3)² = (.8)²    =   .64

(17.1 - 17.9)² = (-.8)²   =   .64

(17.1 - 18.6)² = (-1.1)²  = 1.21

(17.1 - 20.0)² = (2.9)²  =  8.41

Now, sum the values on the right hand side

We have (8.41 + 2.25 + .64 + .64 + 1.21 + 8.41) = 21.56

Now, since this is a "sample," we need to divide this by (the number of values - 1) = (7-1) = (6)

This gives us (21.56/6) ≈ 3.59

Now, take the square root of this   SQRT(21.56/6) = 1.895

And, assuming I didn't make any math errors, that's the standard deviation ... (S.D.)

Now....you might have the same question that I had when I first saw S.D......So what???

Well....what this tells us is how far (on average) each score is from the mean.  A "high" S.D. indicates a "dispersed" data set and a "low" S.D. indicates a data set that is bunched closely around the mean. This data set seems to be fairly closely bunched around the mean.......we don't have any "large" outlier values that would tend to "skew" the S.D. very much. Of course, the terms "high," low" and "closely bunched" are all relative to the situation.

Note....because this process is lengthy, it's usually better to use some sort of application to find S.D.

Here's an app to help you with that:

Yes that is correct - although I would have stuck to (356+1)/2 = 178.5

Middle two pages are 178 and 179 

I put it through Wolfram|Alpha - here is the address

4 apples

log_a(x) = log₁₀(x) / log₁₀(a)

or

log_a(x) = ln(x) / ln(a)

If you want to do it on the Web2 calc this is how

$$(2+1\div 4)\times(3+2\div 3)$$

Hey Chris, the rest of us want to know what the question is too!  I also like to know the language. 

Re: how to calculate the total volume?  (translated from Slovenian)

This is an arithmetic sequence  (AP)

The first time is 4 and the comon difference is 6

Look here to see how APs work

http://www.mathsisfun.com/algebra/sequences-sums-arithmetic.html

There are 6.02*10^23 molecules per mole (it is called avagadro's number)

So, 7.75*(6.02*10^23)= 4.6655*10^24 molecules 

88/9 or 9.77 (repeating)

write a system of equations with the solution (4,-3)

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OK....this isn't so tough to do..... we only need two equations!!

One equation could be

5x - 2y = 26

The other could be

1x - 1y =   7

For reasons I won't go into, I know there is a unique solution to this. And our unique solution is (4, -3).

Check this for yourself/  Also.......this isn't the "only" system that "works." (We could have an infinite number of them!!)

4 You imbecile.

Picture the triangle made by a line from the centre of the earth through to the top of the lighthouse (which I'll call c); a line from the top of the lighthouse to the ship (which I'll call b); and a line from the ship back to the centre of the earth (which I'll call a).  I would prefer to show a diagram here, but I can't as we can't yet upload files!

Since the angle of depression is 30°, the angle, A, between lines b and c is 90° - 30° or 60°.  We can write the cosine rule for this triangle as a² = b² + c² -2bccos(A).

Now the average radius of the Earth is 6371km (according to Wikipedia), so line a is 6371km long.  Line c is the radius of the Earth plus 325ft (=99.06m) so c is 6,371,000 + 99.06 = 6,371,099.06m.  The only unknown in the cosine rule above is b, and we can solve for b to find two mathematical solutions.  These are 6371km and 198.12m.

Clearly it is the smaller value we want here!  So b = 198.12m.

Now we need angle B, the angle between lines a and c. We get this from the sine rule:  sin(B)/b = sin(A)/a. So:

sin(B)=sin(60°)*198.12/6371000 = 2.693*10^-5 

Angle B = sin^-1(2.693*10^-5) or B = 2.693*10^-5 radians (when an angle is very small its value in radians is approximately equal to its sine).  The distance from the ship to the lighthouse along the curve of the Earth is just B*a where B is in radians.  So $${\mathtt{distance}} = {\mathtt{2.693}}{\mathtt{\,\times\,}}{{\mathtt{10}}}^{\left(-{\mathtt{5}}\right)}{\mathtt{\,\times\,}}{\mathtt{6\,371\,000}} = {\mathtt{distance}} = {\mathtt{171.571\: \!03}}$$ metres

This is 562.9ft to the nearest tenth of a foot.

 Alternatively

 Since the distances are relatively small we could assume the surface of the Earth to be flat near the lighthouse, in which case the distance of the ship from the lighthouse is given by 325*tan(60°)ft or

$${\mathtt{distance}} = {\mathtt{325}}{\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}{\left({\mathtt{60}}^\circ\right)} = {\mathtt{distance}} = {\mathtt{562.916\: \!512\: \!459\: \!925}}$$  feet

or 562.9ft.  

Honey please, people have been asking this for ages.

Here are some of the answers; I hope they can help you out:

5+x>5x-11

5>4x-11

16>4x

4>x

Hay un dígito antes del punto decimal, y el resto de los dígitos están después del punto decimal.

Luego, multiplícalo por 10 a la potencia del número de dígitos, menos uno.

Por ejemplo:

12345 en la notación científica es 1.2345 * 10^4
y 1200000 en la notación científica es 1.2 * 10^6

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(oh right, the translation:) 

There is one digit before the decimal point, and the remaining digits are after the decimal point.

Then multiply it by 10 to the power of the number of digits, minus one.

For example:

12345 in scientific notation is 1.2345 * 10 ^ 4
and 1200000 in scientific notation is 1.2 * 10 ^ 6

Using the properties of powers (see the Formulary) and collecting like terms together:

x³*y³*x⁴*y^a = x⁷y^3-a  

If this is to equal x⁷ then the y term must equal 1.  Now y⁰ = 1 so we must have 3-a = 0, or a =3

$$2\frac{2}{5}+2\frac{1}{4} = 2+\frac{2}{5}+2+\frac{1}{4} = 4+\frac{2}{5}+\frac{1}{4}$$

Collect the fractions over a common denominator:

$$\frac{2}{5}+\frac{1}{4} = \frac{2*4}{20} + \frac{1*5}{20} = \frac{8+5}{20} = \frac{13}{20}$$

So, altogether   $$2\frac{2}{5} + 2\frac{1}{4} = 4\frac{13}{20}$$

If I've interpreted the question correctly (a little difficult because of the lack of punctuation!), then:

Let the the original price be P.  The tax is then: tax = 0.08*P.

The discounted price is 0.4P (i.e. 60% less than the original price).  This equals $55, so 0.4P = 55.  Divide both sides by 0.4 to get P = 55/0.4 or P = $137.5.  The tax is therefore: tax = 0.08*137.5, or tax = $11.  The total is then $55 + $11 = $66.

diameter=2*radius

2*4=8

diameter is 8 inches

radius=diameter/2

1/16 is the radius

If the area is 30 square units and the lenght is 6 units simple divide the area by the length

30÷6=5

To make sure this awnser is correct 6x5=30 

Cos(A-B), SinA=3/5 SinB=5/13

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Cos (A-B) = CosACosB + SinASinB

Since we're dealing with "Pythagorean Triples" triangles, CosA = 4/5 and CosB = 12/13

So we have.....(4/5)(12/13) + (3/5)(5/13) =  48/65 + 15/65 = 63/65