Melody

The other method is the stars and bars method

There are 6 stars, they are seperated into 3 groups so we need 2 bars to seperate them

One group is before the bars, one is after and the other is inbetween

so that is 8 'things' and I need to find how many different places the bars can go.

That is

8C2=28

How many ways are there to put 6 balls in 3 boxes if the balls are not distinguishable but the boxes are?

Number in the boxes

6,0,0             3 ways

5,1,0              6 ways

4,2,0              6 ways

4,1,1              3 ways

3,2,1              6 ways

3,3,0              3 ways

2,2,2               1 ways

I get 28 ways

I just get a black screen :(

And he is still a very handsome turkey LOL.   

Find the length of an arc on a circle of radius 8 corresponding to an angle of (90/π)∘

I keep getting the answer of 229.12 but it asks me to enter it as a fraction

When you get answers Roxettna you should learn to look at whether that answer is reasonable.

Here you have a circle of radius 8 so the circumference is 2*pi*8 which is about 50units.

pi is just a bit more than 3 so 90/pi is about 30degrees.  Which is only a little bit of a circle so the answer must be way less than 50.

Your answer of 229 could not possibly be correct!

Now  the circumference of a circle is    2*pi* r

There are 360 degrees in a revolution.

so

you have     90/pi  divided by 360   of the circle

So

\(Arc\; length = \frac{\frac{90}{\pi}}{360}*2\pi r\\ Arc\; length = (\frac{90}{\pi}\div 360)*2\pi r\\ Arc\; length = (\frac{90}{\pi}\times \frac{1}{360})*2\pi r\\ Arc\; length = \frac{1}{4\pi}*2\pi r\\\)

You should be able to finish it from there. Don't forget that r is 8 units    

M, as in macabresubwoofer, does not get help. At least not to learn.

It is more than evident that Web2 is just a cheat site for macabresubwoofer.

And yes, he (possibly she) is abusive to the people who do his homework for him.

You are welcome :)

Yes that is right and if you want to use formula (which shouls also be your second choice with these.)

It will be P(3,3) becasue you are only worrying aobut ordering 3 subjects.

BUT

please understand the logic of these without the forumula.

Then when you do need to use it the formula will make more sense.

Look,

There are 4 choices for the first hour.

one subject is now chosen so there are 3 subjects left.

There are 3 subjects fo the second hour

There are 2 left for the 3rd hour

and only one left for the last hour.

so

4*3*2*1 = how many possibilities there are

What does 4*3*2*1 equal?

Now forget about formulas and tell me how to do part b.