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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?
Pierox
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.
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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?
With 3 people, there are only 3 handshakes: AB, AC, and BC. Where it gets interesting is at a party with, say, 10 people ... 45 handshakes. Or in the US Senate when all 100 Senators are present ... 4,950 handshakes.
How many handshakes if 6 people?
If six people meet there are fifteen handshakes.
At certain party there wereb 45 handshakes Everyone shook hands with everyone else exactly once how many people attended the party?
There were ten people at the party. This is a triangular sequence starting with two people: 1, 3, 6, 10, 15, 21, 28, 36, 45, etc. There's an equation for this. With n people at the party, the number of handshakes is n(n-1)/2.
If theres 66 handshakes how many people are at the party?
If there are n people who shake hands with each other exactly once, it can be observed that there are n x (n-1) handshakes. Since each handshake is counted twice here,we divide this by 2. Therefore, total number of handshakes is n(n-1)/2. In the given problem, Given: Total handshakes =66 i.e n(n-1)/2=66 n2-n =132 n2-n-132=0 (n-12)(n+11)=0 n =12 or n= -11 As handshakes cannot be negative we discard 11 . Therefore answer is , 12 people.
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.
Prove that total number of people who lived on earth and made odd number of handshakes is always even?
If you multiply anything by 2 it always comes out even. So if people make 35 handshakes, we multiply it by 2 and we get 70 people. This will work with any different number of handshakes, odd or even.
there are 3 people at a party if each person mis shake hands with every person at the party exactly once how many handshakes will there be?
So, there will be 3 handshakes among the 3 people at the party.
If at a party there are twelve people present Everyone has to shake hands exactly once with every other person How many handshakes are necessary?
Sixty-six unique, distinct handshakes.
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?
With 3 people, there are only 3 handshakes: AB, AC, and BC. Where it gets interesting is at a party with, say, 10 people ... 45 handshakes. Or in the US Senate when all 100 Senators are present ... 4,950 handshakes.
How many handshakes if 6 people?
If six people meet there are fifteen handshakes.
If ten people met at a party and they all exchanged handshakes how many handshakes were exchanged?
107 unique handshakes will be exchanged
At certain party there wereb 45 handshakes Everyone shook hands with everyone else exactly once how many people attended the party?
There were ten people at the party. This is a triangular sequence starting with two people: 1, 3, 6, 10, 15, 21, 28, 36, 45, etc. There's an equation for this. With n people at the party, the number of handshakes is n(n-1)/2.
If theres 66 handshakes how many people are at the party?
If there are n people who shake hands with each other exactly once, it can be observed that there are n x (n-1) handshakes. Since each handshake is counted twice here,we divide this by 2. Therefore, total number of handshakes is n(n-1)/2. In the given problem, Given: Total handshakes =66 i.e n(n-1)/2=66 n2-n =132 n2-n-132=0 (n-12)(n+11)=0 n =12 or n= -11 As handshakes cannot be negative we discard 11 . Therefore answer is , 12 people.
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.
How many handshakes are there if 100 people all shake hands?
4950 handshakes, that is the definite answer
If at a party there are a total of 741 handshakes and each person shakes hands with everyone else at the party exactly once how many people are at the party?
38
How many handshakes would take place if 1000 people shook each other's hand exactly once?
1000*999/2 = 499500
