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There are 8 people they all shake hands how many hand shakes are there?
Wiki User
∙ 14y ago
There are 28 handshakes if everyone shakes hands with everyone else. It is an arithmetic progression and can be solved with the equation Sn=(1+(n-1))(n-1)/2 where Sn is the total sum of handshakes for n people.
NB: I have used n-1 instead of n in the equation for the sum of an arithmetic progression, because you're not really going to shake hands with yourself, so you don't include the nth term, in this case 8.
Alternatively, you can solve this geometrically by drawing an octagon, drawing lines between all the vertices, and then adding all the lines up.
Wiki User
∙ 14y ago
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If the friends shake hands mutually then the total number of hand shakes is?
one....
How many handshakes will be there be in total if 9 people shake hands with each other?
the first shakes 8 people's hands (remember, not his own), the second 7 (he doesn't shake the first one's hand), then the third shakes six, the fourth shakes 5, the fifth shakes 4, the sixth shakes 3, the seventh shakes 2, and the 8th shakes the 9ths hand so 8+7+6+5+4+3+2+1 = 36
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?
If there are seven people, then the number of handshakes is 7*6/2 = 21
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.
If 6 people shake hands with each other how many hand shakes is that?
the answer is 15 not 21....because the total no. of handshakes will be (5+4+3+2+1) not (6+5+4+3+2+1) as the 1st person will have only 5options 2nd will have 4 options n so on...also we can calculate the answer by combination..that is 6C2.
There are 10 people they all shake hands how many hand shakes are there?
45 handshakes
There are 9 people they all shake hands how many hand shakes are there?
36. Everybody shakes 8 hands but each shake counts for 2 people. So 9*8/2=36.
If there are 100 people at a party and they all shake hands once how many hand shakes will there be?
4950
21 people shake hands with each other How many hand shakes are exchanged?
210
How many hand shakes if 12 people shake hands with every other person in room?
72
There are 15 people they all shake hands how many hand shakes are there?
105 ( First person shakes 14 different hands, second shakes 13 etc etc down to 14th shakes 1 hand. Sum of 1 to 14 = 105.)
If the friends shake hands mutually then the total number of hand shakes is?
one....
How many handshakes will be there be in total if 9 people shake hands with each other?
the first shakes 8 people's hands (remember, not his own), the second 7 (he doesn't shake the first one's hand), then the third shakes six, the fourth shakes 5, the fifth shakes 4, the sixth shakes 3, the seventh shakes 2, and the 8th shakes the 9ths hand so 8+7+6+5+4+3+2+1 = 36
How many hand shakes would take place if 20 people shake hands once?
First person shakes hands 19 times, second person 18 etc, a total of 190.
If seven people are in a room and they shake hands with each other once how many hand shakes would take place?
20 hand shakes would take place. Here's how: 1234567 23456 34567 4567 567 67 7 And a person can't shake his own hand or someones hands twice
How many hand shakes would take place if 14 people shake hands once?
If each person is shaking with only one hand, then the answer is seven. If they are shaking with both hands, then the answer is 14.
If 2000 people shake hands once with everyone in the room how many hand shakes would take place?
1 999 000
