[lneagos]

Two cards are drawn from a standard deck of 52 cards. Find the probablity of both cards either red or a king.

[galactus]

A good way to do this is to find the probability of drawing no Kings or no Reds and subtract from 1.

Remove the Reds and Kings and there are 24 cards left, choose 2: C(24,2)

[ebaines]

Thois one is pretty straight forward. In a standard deck there are 28 possible "winners" on the first draw (26 red cards plus 2 black kings). If that first draw is successful, then there are 27 winners out of the 51 cards that are left on the second draw. So the prob of both being either a red or a king is simply

[galactus]

Here's a link to a similar problem. It uses black or an Ace, but it would be the same.

Free Math Help.com - Homework Help! :: View topic - Adding Probability

[Jersey27]

What you need to do is add up the red cards and the 2 extra kings. You should get 13 hearts, 13 diamonds, and 2 extra kings. That then will give you 28 out of 52 or 28/52 which gives you .5384...

[galactus]

what you need to do is add up the red cards and the 2 extra kings. You should get 13 hearts, 13 diamonds, and 2 extra kings. That then will give you 28 out of 52 or 28/52 which gives you .5384...

That would be true for the one card, but the problem states 2 cards.

Another way to look at the above problem is:

[rsoucy5]

Calculate the surface area of a sphere in cmsquared if the radius is 6cm.

[galactus]

Please create a new thread for a separate question.

BTW, the surface area of a sphere is given by

Plug away.