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## Question

now think about this. say the reporter wanted to find out how many cobinations one person could have shaken hands, how many ways are there?

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39!

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not sure what you mean by "combinations"...do you mean in what order he shook the hands of the other 39 people? if so the answer is

741 which is 39*38*37...*1

if you mean how many times did he shake hands, then the answer is of course 39.

the formula for how to figure out how many hand shakes is as follows.

let n equal the number of people who are shaking hands.

the number of handshakes is n*[(n-1)/2]. this will give you the number no matter how many people are in attendance. if your number is 500, then 499/2 = 249.5 and 249.5*500 = 124750 which the total number of handshakes. this works for any combination problem, where you take a number and multiply by one less, and then again and again all the way down to 1.

let me know how I did, or if I was way off base by what you meant by "combinations"

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not sure what you mean by "combinations"...do you mean in what order he shook the hands of the other 39 people? if so the answer is

741 which is 39*38*37...*1

if you mean how many times did he shake hands, then the answer is of course 39.

the formula for how to figure out how many hand shakes is as follows.

let n equal the number of people who are shaking hands.

the number of handshakes is n*[(n-1)/2]. this will give you the number no matter how many people are in attendance. if your number is 500, then 499/2 = 249.5 and 249.5*500 = 124750 which the total number of handshakes. this works for any combination problem, where you take a number and multiply by one less, and then again and again all the way down to 1.

let me know how I did, or if I was way off base by what you meant by "combinations"

yes there were 39 "shakes", but in which order? he could have shaken hands with #8 or #15 first, #9 or #28 second, and so one. u have the answer. but what about how many orders of shakes in all? so if #1 shook hands with #8 first, #8 also shook hands with #1 first. then #1 shakes hands with #7, so #8 can shake hands with anyone but #1 (already shaken) or # 7 (hes already shaking hands. but maybe if he wants to shake hands with #5, #5s already shaking hands with #12 or #21. so how many combinations in all?

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ok...i see what you are saying...i think the answer would be

a s*** load...or maybe a hell of a lot.

lol...i have no idea...that's a good one tho.

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ok...i see what you are saying...i think the answer would be

a s*** load...or maybe a hell of a lot.

lol...i have no idea...that's a good one tho.

haha very true! thanks!

i truly have no idea either! maybe someone out there can help...

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haha very true! thanks!

i truly have no idea either! maybe someone out there can help...

post #1

Select one guest, he can shake hand first time with 39 other guests, the other handshakes doesn’t matter between the other guests, maybe our selected guest have to wait..for the second handshake he choose from 38 guests, together 39*38 possibilities, and so on...

39*38*...*2*1 = 39! = 20397882081197443358640281739902897356800000000

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post #1

Select one guest, he can shake hand first time with 39 other guests, the other handshakes doesn’t matter between the other guests, maybe our selected guest have to wait..for the second handshake he choose from 38 guests, together 39*38 possibilities, and so on...

39*38*...*2*1 = 39! = 20397882081197443358640281739902897356800000000

i think you basicly understand it. to refrase it, lets just say they all line up in a line. #1 goes down the line. first handshake, second handshake...onto the end. then #2 goes down the line, and shakes hands with everyone except #1. this is because #1 already shook hands with him/her. though this is a different answer to the problem before (now #7's 3rd handshake and #9's 3rd handshake can be the same. before, everyone shook hands at the same time. now, its one shake at a time.

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