If the four men are the only men in the room : 24 If there are other people in the room: it depends on amt. of others

6 handshakes. The people are A, B, C, and D. A-B. A-C. A-D. B-C. B-D. C-D.

i say 12.lol or just 3

6. *-* |X| *-*

Good points about before and after (formality bit) the number of handshakes (assuming just the once per couple) can be calculated using the formally x=n*(n-1)/2 Where x = the number of handshakes and n = the number of people. So for 4 people.. x = 4 * 3 / 2 = 6 If there were 10 people then it owuld be 45 (As a new person enters the room - then he has to shake hands with everyone in the room so its 1 + 2 + 3 + 4 + .... + n. The formulae calculates this sum.

12

This question can be rephrased: How many ways can two different people be chosen from a group of four? (Let's assume that once two of the four are chosen, they have to shake hands.) This is simply the combination problem "4-choose-2", usually represented as 4C2 (you can think of it as "out of 4, how many ways can I choose 2?"). In this problem order does not matter because we consider A and B having shook whether "A shakes B's hand" or "B shakes A' hand"--in other words, once this shake occurs we don't count it again if it occurs the other way--it's already been counted. (If order did matter, and "A shakes B's hand" would be considered different than "B shakes A's hand," then you'd want to consider it a *permutation* problem, not a *combination* problem.) The formula for nCr is: nCr = n!/(r!*(n-r)!) So: 4C2 = 4!/(2!*2!) = 4*3*2*1/(2*1*2*1) = 4*3*2/(2*2) = 4*3/2 = 2*3 = 6 This is a different way of stating the same problem: Say you have an urn full of n chips, each numbered with a different value 1 through n. You draw r chips from the urn and write the numbers in ascending order. How many different sequences can be drawn from the urn? The answer: nCr (see formula above).

A-B A-C A-D B-C B-D C-D That's six.

4C2=6 By principle of combination.(Permutations and combinations)

You got the obvious one, and the one that is usually right as 6. However, this question is stated very vaguely and does not truly give enough details. Did they all manage to do one huge handshake together so it is one? Did the four men meet in one room, and yet, they were in sets of two, so only the men who did not know each other shake hands, thus just switching and having two handshakes occur? There are so many possibilities with the question you stated that you are going to get a lot of answers, but usually 6.

I don't know the amount of hand shakes that go on but the germs that just got spread around that circle are in the millions

6, I draw a picture. Just like I use to do in kindergarten. took all of 20 seconds.

6, did it in my head as my brain works like that, i.e. "Man 1 shakes with men 2,3,4, then man 2 shakes with 3 and 4, and man 4 shakes with 3"

6 / or twelve if they shake with both hands to each other - so the dude at the bottom might be right - haha!

Do they shake just their left hands?Or their rights with their left hands?or their left hands with their right hands?Or just right hands? Ull have to be more specific