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27 = 100% how much % is 17?

\(x\% \;of\;27=17\\ \frac{x}{100} \;\times\;27=17\\ \frac{x}{100}=\frac{17}{27}\\ x=\frac{17}{27}\times 100\\ x\approx 62.96\% \)

check

62.97/100*27 = 17.0019     near enough :)

Thanks Bertie,

I think it is better now ?

You might want to take another look at that last line Melody.

Bertie

Excellent answer Dragonlance but don't forget your units.

I know there are none in the question but you should add units and units³  anyway   

Sat   2/1/16

1)  The moderators and most of the members and guests here really like that this is an international site and     that not all questions are asked in English!  Every well intentioned person is welcome here!

     https://web2.0calc.com/questions/arghhhhhhhh#r9

2)  It is amazing what unlikely posts can result in good social interchange.

     https://web2.0calc.com/questions/f-this-site

3)  Jokes and Riddles     Thanks Guest :)

     https://web2.0calc.com/questions/jokes-and-riddles

4)  Is Googol a number?  Thank Alan

    https://web2.0calc.com/questions/what-the_2

5)  Calculate pi to 6 places with only very basic calculator    Thanks Guest

     https://web2.0calc.com/questions/calculate-pi

6)   Integrate sin^4x  This is a repetative question, one students at this level should  be able to answer.

     Thanks CPhill and guest.

     https://web2.0calc.com/questions/indefinite-integral_1

!! HAPPY NEW YEAR !!

@@ What is Happening?  [Wrap4]   Fri 1/1/16   Sydney,  Australia Time 8:45 pm   ♪ ♫

Hi all, 

It is already busier, too bad I like it quiet but that is ok :)  We has some great answers from geno3141, Complex, gibsonj338, Alan, Dragonlance and Bertie.  Thanks all    

Technical Issues:

How can you post a picture when the picture upload on the forum is not working properly ?

Thanks very much Alan for these instructions.

My first math answer for this year:)

Take the cuberoot of the cube volume to get the side length.

\(\sqrt[3]{1000} = 10\)

Diagonal of a cube is

\(s*\sqrt{3} = d\\ 10*\sqrt{3} = 17.32 \)

That is equal to the diameter of the sphere

Now take half that for the radius

\(\dfrac{17.32}{2} = 8.66\)

Then the volume of the the sphere is

\(\dfrac{4}{3}\pi * 8.66^3 = 2720.5 ~ units \)

So the smallest sphere that will hold a cube of 1000 is 2720.5 units

The Wikipedia article on Fourier transforms might help answer some of your questions (https://en.wikipedia.org/wiki/Fourier_transform).  Here is a copy of part of its first paragraph. I've highlighted a couple of parts related to your questions.  

The Fourier transform decomposes a function of time (a signal) into the frequencies that make it up, similarly to how a musical chord can be expressed as the amplitude (or loudness) of its constituent notes. The Fourier transform of a function of time itself is a complex-valued function of frequency, whose absolute value represents the amount of that frequency present in the original function, and whose complex argument is the phase offset of the basic sinusoid in that frequency. The Fourier transform is called the frequency domain representation of the original signal.

To help understand the relationship between the time domain signal and the corresponding fourier transform domain result, try constructing a wave form yourself by adding together a couple of sine waves of different amplitude and frequencies and then applying a fourier transform to the result.  

A signal comprising the sum of pure sinusoids will be zero everywhere except at the frequencies of the sinusoids.  More general signals (e.g. sin(w*t)*e^-t) will have more components in the frequency domain.

Hi Guest, You have to be a member to post pictures.   

That is really easy. You need to chose a username and a password and you need to give a valid email address.  That is it!

Once you become a member just follow Alan's instructions on how to post a picture.  I have been including the post reference in Every Wrap for quite a while now (the post before and after this will have it) ! (Under Technical Issues)  I look forward to seeing you as a member :)

Lets look at them one at a time

A and D have right angles - I'll look at them first

The two short sides for A are in the ratio  2:3

The two short sides for D are in the ratio  6:9  which simplifies to 2:3

SO

A and D are similar

Now I will look at  B and C

The shortest side of B to the shortest side of C is 2:3

I can see that the angles are not the same. So they are not similar.

Thanks Guest, 

I just want to play too.    

\(\frac{dx}{dt} * x^ 2 = e^{2t}\\ x^2\frac{dx}{dt} = e^{2t}\\ \int x^2\frac{dx}{dt}\;dt = \int e^{2t}\;dt\\ \int x^2\;dx = \int e^{2t}\;dt\\ \frac{x^3}{3} = \frac{ e^{2t}}{2}+c_1\\ x^3 = \frac{ 3e^{2t}}{2}+c_2\\ x=\left [\frac{ 3e^{2t}+c_3}{2}\right]^{1/3}\\\)

Last line has been edited.

Actually this is a really good 3 dimensional question !

Some of our members may like to have a go at it!  

So long as you know how to find the volume of a sphere   V=(4/3) pi*r^3

and the volume of a cube  then you can try it !!

HINT: You may need to use the Pythagorean Theorem too!

I just want to look at these methods, especially Bertie's method   

11000000111001

 #3 Guest

Better is to use the 'double and add the next digit' method.

Consider an easier example first.

1011 -> 8 + 0 + 2 + 1 = 11

Start with the 1 at the left hand end, double it and add the next digit, 2*1 + 0 = 2, double that and add the next digit, 2*2 + 1 = 5, double that and add the next (the final) digit 5*2 + 1 = 11.

Try another one, 110101 (-> 32 + 16 + 0 + 4 + 0 + 1 = 53).

On paper, it's usual to set it out in a column

1     1

1     1*2 + 1 = 3

0     3*2 + 0 = 6

1     6*2 + 1 = 13

0     13*2 + 0 = 26

1     26*2 + 1 = 53.

If you look in 'Sticky Topics - Great Questions to Learn From', there's a note regarding the conversion of decimal to binary, this is the reverse operation.

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

110101 = 2^5+2^4+2^2+2^0 = 32+16+4+1 = 53

Bertie's Method :  Starting from the LEFT
\(110101_2 \\ = (((((1*2+1)*2+0)*2+1)*2+0)*2+1) \\ = (((( 2^2+2+0)*2+1)*2+0)*2+1)\\ =(((2^3+2^2+1)*2+0)*2+1)\\ =((2^4+2^3+1*2+0)*2+1)\\ =2^5+2^4+2^2+1\\ =32+16+4+1\\ =53\)

I learned to do the decimal to binary this way (in reverse).  And I like that method.

I think I learned it from Heureka but it could have been from you.

BUT

This is really weird Bertie, I can see that it works but I think most school students would be better off to make sure that  they understand Our German guests methods.  That is how they would normally be taught at school and it is much more intuitive.  

Now I might as well try to do the original question this way:

11000000111001    14 digits  

I am going to use the table tab that is provided for us in the ribbon with 14 rows

Ok I got the same as our first guest that is great!

NOW i am going to do it MY way - A different way again!

I am going to change it to hexidecimal FIRST

By grouping the digits into 4s starting from the RIGHT     

11   0000   0011   1001 = 3 0 3 9 base 16

\(3*16^3 + 3*16 + 9 = 12288+48+9 = 12345   \)   

If you want me to explain this better then just ask  

Thanks for showing us your method Bertie  ,

I never would have thought to do it like that. :))

6cm * (x+2y) =  ( 6x+12y ) cm

F (t) = 5 cos (pi/4 t) + 11

You want to know what it looks like?

1) Well it is a cosine curve

2) The wavelength is  \(2\pi\div\frac{\pi}{4} = 8\)

3) There is no phase shift

3) The amplitude is 5

4) the curve is raised 11 units making the centre of it  y=11

Here are the graphs

Hahaha, I had to read your message about a dozen times before i realized what you were talking about Naus.

I never even considered that anon might be you!!    I knew that anon was both smart and sweet so he could not have been you!!  ROF LOL

Thanks Bertie, it is always a great pleasure having you on the forum.  You must remember to sign your name at the beginning of our posts though!

A Very Happy New Year to you both.      

The caret or hat  ^  is a universal symbol for 'to the power of'.

I don't understand your problem with it ?????

Thanks Solveit, Rosala, Gliu1 and guest.     

Guest, I was going to tell you where Roasala lives but she should probably do that herself if she wants too.

Unfortunately she may not see your message.  soooo

Here is a time map

A ladder is placed 4 feet from the base of a building. The ladder reaches a height of 12 feet. What is the length of the ladder? Round your answer to the nearest tenth. Explain your answer.

Use Pythagoras's Theorem, which says: The square of the Hypotenuse=The sum of the squares of the other two sides. Since we have the value of the other two sides, therefore:

H^2=4^2 + 12^2

H^2=16 + 144

H^2=160 take the square root of both sides, and we have:

H=sqrt(160)

H=~12.65 feet-Length of the ladder.

Hello there! May I ask if you are a college student, and if so what year? Go through this interactive essay of FT and be patient and read it slowly and leisurely. It just might answer SOME of your questions. The only "Moderator" here that might be able to answer your questions is "Alan" . You will probably not be able to get him until Monday, Jan. 4, 2016. Good luck to you:

http://betterexplained.com/articles/an-interactive-guide-to-the-fourier-transform/

Simplify the following:
534773×67-83954

|  | 5 | 3 | 4 | 7 | 7 | 3
× |  |  |  |  |  | 6 | 7
| 3 | 7 | 4 | 3 | 4 | 1 | 1
3 | 2 | 0 | 8 | 6 | 3 | 8 | 0
3 | 5 | 8 | 2 | 9 | 7 | 9 | 1:
35829791-83954

|  |  | 7 | 12 | 8 | 17 | 8 | 11
| 3 | 5 | 8 | 2 | 9 | 7 | 9 | 1
- |  |  |  | 8 | 3 | 9 | 5 | 4
| 3 | 5 | 7 | 4 | 5 | 8 | 3 | 7:
Answer: | 35,745,837

√(72.1 + (14 - 6.7) cubed

First, your brackets mismatch!. Is this what you want: sqrt(72.1) + (14 - 6.7)^3  ?????????????????.

Write it clearly, so that we can you the right answer.

By the way, you can raise any number to any power by using the power key "x^y" just below "e". Example: 1.25^3= First enter 1.25, the press "x^y", then enter 3 followed by = key. That should give you:1.953125.

Factor the following:
x^3+4 x^2-5 x

Factor x out of x^3+4 x^2-5 x:
x (x^2+4 x-5)

The factors of -5 that sum to 4 are 5 and -1. So, x^2+4 x-5 = (x+5) (x-1):
Answer: | x (x+5) (x-1)

It's just as messed up to me as it is to you bro.😪 there are so,e things I don't even pretend to understand XD

They didn't even include Stitches * sobs uncontrollably*