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If there are seven people, then the number of handshakes is 7*6/2 = 21

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Q: Seven people come to a party and shakes hands with each other if each person shakes the hand of every other person how many hand shakes occur?
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If there are 8 people at a party and every person shakes hands with everyone else at the party how many handshakes will there be?

There will be 28 handshakes. If you ask each person how many handshakes they had they will tell you 7 making 7 x 8 = 56 handshakes in all. But every hand involves two people, so every handshake has been counted twice, thus there are 56 / 2 = 28 handshakes in all.


There are five people in a room Each person shakes the hand of every other person exactly once How many handshakes are exchanged?

Everyone shakes hands with 4 other people. Since there are 5 people in the room this would suggest there are 5*4 = 20 handshakes. However, you would then be double counting handshakes: A shaking hands with B and B shaking hands with A is, in reality, only one handshake. Thus there are 5*4/2 = 10 handshakes in all.


At a meeting every person shook hands with every other person exactly 1 time and there were a total of 28 handshakes then find the number of people at the meeting?

8 Explanation: The general formula for the number of handshakes is n(n-1)/2 where we have n people shaking hands with n-1 other people. so 28=n(n-1)/2 or 56=n^2-n the solution to this comes from solving n^2-n-56=0 so this factors as (x-8)(x+7) and the answer is 8 To understand this formula think of a small number, like 3 people Each person can shake hands with 2 other people. Let us call the people A, B, and C AB mean A shakes hand with B But AB=BA since if A shakes hands with B then B certainly shakes hands with A But if we look at all the possibilities we have AB, BA,BC, CB, AC and CA, as we explained this double counts so we divide by 2. 3(3-1)/2=3 as expected from the explanation above.


How many handshakes if 20 people shake hands with every other person in the room?

190


If There are 3 people at a party If each person must shake hands with every other person at the party exactly once how many handshakes will there be?

3. AB, BC and CA.

Related questions

How many handshakes if 6 people shakes hands with every other person in the room?

If there are 6 people in a room, and each person shakes hands with every otherperson in the room, then there will be 15 separate and distinct handshakesbetween different pairs of people.


How many hand shakes if 12 people shake hands with every other person in room?

72


How many handshakes if 4 people shakes hands with every other person in the room?

Type your answer here... 6


Five people shake hands with every one how many shakes were there?

25 shakes


How many handshakes for 50 people?

If each person shakes the hand of every other person just once, then 50*49/2 = 1225


How many people are there if everyone shakes hands and there are 66 handshakes?

Assuming that each person shakes hands with every other person, there are 12 people. Let n be the number of people. Then each person shakes hands with (n-1) people and if you ask every person how many hand shakes they made and total them you will get a total of n(n-1) handshakes. However, each handshake involves two people and has been counted twice - once by each person that shook hands - thus number of hand shakes is half of this, giving: n(n-1)/2 = 66 ⇒ n(n-1) = 132 ⇒ n2 - n - 132 = 0 ⇒ (n - 12)(n + 11) = 0 ⇒ n = 12 or -11 You can't have -11 people, therefore there are 12 people.


Examples of hard riddles or quizzes?

if there are 2 people in a room and each one shakes hands once with every other person in the room, how many hand shakes are there?... answer( 1 handshake) pretty easy isn't it? if there are 3 people in a room and everyone shakes hands with everyone else, how many hand shakes are there? answer( three handshakes) now how many handshakes will there be for 5 people in a room? its your time to shyne...


How many handshakes if 100 people shake hands with every other person in room?

Perhaps 9,900 As in you shake with 99 other people, then the next person does the same. So each of the 100 people do 99 shakes. 99 x 100 = 9,900


How many handshakes will there be in total if 10 people shake hands with each other?

"Each other" leaves this very open-ended; that depends on if A shakes with B or A shakes with B & C, OR if A shakes with all the other nine, etc. I would say the answer would have to be one of two: 10 or 100. If each person chooses only one to shake with, it would be ten. IF each person shakes with everyone there, all ten, it would be 100. Since this question is pretty vague, Some people may come to the conclusion that the answer is Either 90 assuming everybody stayed to shake hands with each other meaning the first person shook hands with 9 people and the 2nd person did the same etc etc bringing it to the conclusion that you got 90 handshakes. Another answer towards for people would be 45 being that the first person gave a hand shake to 9 people and then left and then the 2nd person gave a handshake to 8 people n then left etc and etc making it 9+8+7+6+5+4+3+2+1=45. A very simple formula can be applied here. no. of handshakes= (n(n-1))/2 where n is the no.of people present Another conclusion i think the answer is, is the simplest conclusion you can come up with; at the end of the banquet 10 people shake hands with each other so how many handshakes were passed on? 5 hand shakes were given cause that way 10 people did give a hand shakes and since it takes 2 to give out a handshake 5 hand shakes were given. The phrase "Each other" is inclusive, meaning that every person shakes the hand of every other person at the end of the banquet. And since the handshakes that occur when person 1 shakes person 2's hand and vice versa, are the same handshake, those handshakes only count as one entire handshake. This holds true with every other handshake between every other person at the banquet. With this is mind, there will be 45 handshakes since person 1 will shake 9 other people' hands, then person 2 will shake 8 other people's hands, and so on. It would look like this on paper: 9+8+7+6+5+4+3+2+1=45. Each of the 10 people shakes hands with 9 others. If you multiply that, you are counting each handshake double. Therefore, the calculation is 10 x 9 / 2.


If there are 8 people at a party and every person shakes hands with everyone else at the party how many handshakes will there be?

There will be 28 handshakes. If you ask each person how many handshakes they had they will tell you 7 making 7 x 8 = 56 handshakes in all. But every hand involves two people, so every handshake has been counted twice, thus there are 56 / 2 = 28 handshakes in all.


In a party everyone shakes hand with each other. If total number of handshakes is 780 how many people were there?

There were 40 people at the party. Let n be the number of people at the party. Each person shakes hands with every other person, so each person shakes hands with (n - 1) people, a possible total of n(n - 1) handshakes. But when person A shakes hands with person B, B also shakes hands with A, so each handshake would be counted twice. → number_of_handshakes = n(n - 1)/2 total number of handshakes is 780 → n(n - 1)/2 = 780 → n(n - 1) = 1560 → n^2 - n - 1560 = 0 As 1560 is negative, one factor is positive and one is negative, so we need the factor pair of 1560 which has a difference of 1, namely: 39 x 40 → (n - 40)(n + 39) = 0 → n = 40 or -39 There cannot be a negative number of people → there are 40 people present.


At the end of a banquet 5 people shake hands with each other How many handshakes will there be in total?

Each person shakes hands with every other person at the end of the banquet. When person 1 shakes hands with person 2 that constitutes one handshake even though 2 people are involved. So the answer is 10 total handshakes because the 1st person will have 4 total handshakes(because he can't shake hands with himself, he has 4 and not 5 total handshakes), and then the 2nd person will have 3 total handshakes (you wouldn't say 4 handshakes because you've already included the handshake between person 1 & person 2 when calculating the first person's number of shakes) and so on for the remaining 3 people. On paper the math would look like this: 4+3+2+1=10 Alternatively: Each person shakes hands with 4 others so the answer looks like 5x4 = 20; However, in Fred shaking with 4 others, he shakes with Charlie, similarly, in Charlie shaking with 4 others he shakes with Fred. Thus the Fred-Charlie handshake has been counted twice (once by Fred, once by Charlie), as have all the handshakes, thus the answer is: 5x4 / 2 = 10.