ok the problem is this: Seven people meet and shake hands with one another. how many handshakes occur?
2007-09-07 08:59:21 · 11 answers · asked by Kiid23 3 in Education & Reference ➔ Homework Help
n(n-1) / 2
n is the number of people.... in this case it is 7.
You multiply the number of people (n) by (n-1) which eliminates shaking hands with yourself. Than you divide by two to get rid of duplicate handshakes. For example: If only two people are in the room then there is only one handshake, but if I DON NOT divide by two in the formula the handshake will be counted twice.
Hope this helps. I teach mathematics and all though this MAY seem a bit confusing now if you just think about it.... I KNOW you will get it.
2007-09-07 09:06:00 · answer #1 · answered by michelle s 3 · 0⤊ 0⤋
Lets assume they shake hands only once.
Let's call them A, B, C, D, E, F ad G
A shakes hands with B C D E F and G , 6 shakes
B shakes with C D E F and G 5 shakes
C shakes with D E F and G 4 shakes
D shakes with E F and G 3 shakes
E shakes with F and G 2 shakes
F shakes with G 1 shake
Total 6 + 5 + 4 + 3 + 2 + 1 = 21
2007-09-07 09:06:39 · answer #2 · answered by quatt47 7 · 1⤊ 0⤋
21 handshakes
6+5+4+3+2+1=21
if you take 1 person they can shake 6 poeples hands then they can shake 5 peoples hands then 4 and so on.
2007-09-07 09:05:34 · answer #3 · answered by Anonymous · 0⤊ 0⤋
7*6/2 = 21
2007-09-07 09:31:48 · answer #4 · answered by 7 · 0⤊ 0⤋
Seven people meet and shake hands with one another.
So each person shakes hands with six people.
Seven x six = Fourty two handshakes
I hope they washed their hands afterwards.
2007-09-07 09:33:05 · answer #5 · answered by pink 6 · 0⤊ 0⤋
21 handshakes.
2007-09-07 09:31:24 · answer #6 · answered by TTU fan 2 · 0⤊ 0⤋
21 handshakes occur..
i drew little circles to represent ppl and drew lines connecting them. so its 21
the first one is wrong. she squared it....u cant shake hands with yourself, so its wrong.
2007-09-07 09:04:17 · answer #7 · answered by tazmaniandevil923 3 · 0⤊ 0⤋
draw a diagram.
sally shook hands with bob, tom, george, sheldon, frank, and lucy.
bob shook hands with sally, tom, george, sheldon, frank, and lucy.
tom shook hands with bob, sally, george, sheldon, frank, and lucy.
and so on...
name all the ppl. it's fun. and it make's it so much easier than numbers... (well maybe not but it's still funner)
2007-09-07 09:09:52 · answer #8 · answered by Anonymous · 0⤊ 0⤋
ya its 21
2007-09-07 09:03:47 · answer #9 · answered by yahoo 2 · 0⤊ 1⤋
21
Let the people be called a,b,c,d,e,f,g
- means shakes with
a-b
a-c
a-d
a-e
a-f
a-g
b-c
b-d
b-e
b-f
b-g
c-d
c-e
c-f
c-g
d-e
d-f
d-g
e-f
e-g
f-g
Everyone has shaken hands with everyone here.
2007-09-07 09:46:33 · answer #10 · answered by Anonymous · 0⤊ 0⤋