If you make the table, there are 26 such numbers that make this true.   

This animated graphic is my favorite.

This gives an idea of the light and shadow and the knowledge and imagination of the science and mathematics that is Euler.

Might be a ninja meteorologist when I grow up!

There are three ways to draw two blue marbles and a red one: RBB, BRB, and BBR. Since there are no overlapping outcomes, these are distinct cases and their sum is the total probability that two of the three drawn will be blue. The desired probability therefore is

(10/16)(6/15)(5/14) + (6/16)(10/15)(5/14) + (6/16)(5/15)(10/14) = 15/56

Your intelligence  or  Miss Melody’s?

Therfore the middle term would be -10x

What time zone is all of you guys in??

HAPPY NEW YEAR TO EVERYONE

(x-5)^2     expands to   x^2 - 5x - 5x + 25  =  x^2 -10x +25      Do you need more info?

336 divided by 12=28!

100,574,555 divided by 67=1501112.76119

35, or 7! / 3!*4!. This is equal to the number of ways that a group of 3 objects can fill seven cells,

with the remaining 4 objects mixed in.

Here's another approach to Melody's answer:

Number of ways to choose a  committee composed of all girls or boys  = 2C(10,4)

Number of possible committees   = C(20,4)

So......the probability that at least one girl or boy is on the committee  =

1   −   2C(10,4)  / C (20,4)    =  1  − 420 / 4845  =  1  − 28.323  = 295 / 393  

Hey Melody....Happy New Year Down Under!!

I used to live in Alaska....now I am in Colorado, but we still have a Polar Bear Plunge every Jan 1st for the people who want to 'cleanse' to start off the New Year !    Ya get a free t-shirt.....who could say 'NO!'     LOL

Where do you live EP ?  North U.S.  somewhere i am guessing.  :)

There are no polar bears near my house, and the only ice is in the freezer.  :(     :)

Happy New Year to everyone on Web2.0Calc......!!!!!

7 am for us here...gearing up for a party!   Anyone up for a swim?

The Grammar club has 20 members: 10 boys and 10 girls. A 4-person committee is chosen at random. What is the probability that the committee has at least 1 boy and at least 1 girl?

BGGG

BGBG

BBBG

This is the sameas saying there can be 1boys, 2boys or 3 boys 

so the only thing there cannot be is   BBBB or GGGG

\(\begin{align}\\P(4 boys)& = \frac{10}{20}\times \frac{9}{19}\times \frac{8}{18}\times \frac{7}{17}\\ &=\frac{14}{323}\\ P(4 girls)&=\frac{14}{323}\\ P(4boys \;or\; 4 girls)&=\frac{28}{323}\\ P(not\;all\;the\;same\;s*x)&=1-\frac{28}{323}\\ &=\frac{295}{323} \end{align}\)

What's 32 percent of 250

32% means = 32/100 =0.32

0.32 x 250 =80.00

You have to have a solid knowledge in Mathematics, and more specifically, in a number of branches of Mathematics such as Algebra, Calculus, Trigonometry, Geometry, Number Theory,Statistics, Probability theory.....etc, and the ability to explain your solutions as thoroughly as possible. Also, the ability to reason using good logic, such as when solving "word problems". As well, a good and solid understanding of the Sciences, such as Physics, Chemisty....etc., would be very helpful. At least, that is my understanding! Somebody could correct me on this!!.

(3/7x + 4/7) - (1/3x -1/2)

You can do this on the web2 calc.  I will put it straight into the calculator here :)

((2*x)/21)+(15/14) = ((2*x)/21)+(15/14)

LOL  :)

Is there any kind of graphical representation of the world-famous formula of e^pi i equals to -1?

\(e^{i\theta}=cos\theta+isin\theta \)

sometimes it is called   \(cis\theta\)

so  

Here is a general picture (not for pi radians  BUT the angle must be measured int radians)

This is referred to as the unit circle on a complex grid..  The centre is (0,0)  and the radius is  1 unit.

The horizontal unit is real

and the vertical unit is imaginary

so if theta = pi radians     

Look here if you would like to work through a little more cool mathemathics :)

See my corrected reply at http://web2.0calc.com/questions/need-asap_1#r3

.

You are right - my answer above is incorrect!

Further thought suggests that it should be:

p(at least 1 boy and 1 girl) = 1 - (number of ways of choosing 4 boys from 10  +  number of ways of choosing 4 girls from 10)/number of ways of choosing 4 people from 20)

or:

p(at least 1 boy and 1 girl) = 1 - 2*nCr(10,4)/nCr(20,4) → 295/323 → 0.913