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5

16 people...
16th person = 15 handshakes 15th person = 14 handshakes
15+14+13+...+1 = 120

5 people were at d party because 5! = 120

Iamdagreatguy:
Weekend brain drill. The first to get the answer wins a prize:

At a birthday party, everyone shook hands with everybody else. There were 120 handshakes. How many people were at the party?

Ans=60

My answer is 16....see it dis way:

16 guest lined up and one @ the end of it shakes the remaining 15 and leaves, then next in line shakes the remaining 14 and leaves also till the last. It will be like 15+14+13+12+........2+1=120.

16 dudes made d party!

15

240

ans is 120,,,,, where is my price?

Iamdagreatguy:
Weekend brain drill. The first to get the answer wins a prize:

At a birthday party, everyone shook hands with everybody else. There were 120 handshakes. How many people were at the party?

15people

5

Hitter:
A

Almost cannot kill a bird. :PP Lol

Almost on front page....try again later

Iamdagreatguy:
Still waiting for more answers

The correct nswer is 16 people.

Seun:
6.

Fail. You did factorial like I did

The answer is 11. If 11 people shock hands. It means 11 x 11. Which is 121 minus u since u can't shock hand with urself which is 120.

15 simple

60

16 people.

Imagine them all in one line. 16th person comes out and shakes 15 people.

15th person comes out. He cannot shake himself or the 16 th person, since he has already shaken him. So he shakes 14.

14th person shakes 13.
13th person shakes 12...

Total shakes = 15+14+13+....+1 = 120.

16 simple

N(N -1)/2 = 120
N(N -1) = 240
16(15) = 240


16 people

10

The answer should be 16.
Use the method of combination.
It's just like u r selecting a group consisting 2 persons each from 'n' of people. Then the equation bcoms 'n' combination 2 equals 120,which gvs the value of n to be 16

drdaniels:
its definitely 16..

Chief A would shake hands with 15 people. Alhaji B would shake hands with 14 people since he had already shook Mr A's hands. Dr. C would shake hands with 13 people coz he had shook hands with both Chief A and Alhaji B

I go with dis

15 people

16 is the answer.

More like solving for 15! but using the addition operation in place of the multiplication operation.

Brain is drilled already ...after 6 bottles of gulder. Lets fi le it tomorrow

120 hand shakes, means there was a total of 240 hands that took part.

if there where 16 people, one person will shake 15 other hands, (240 hands in total)

thus the answer is 16.

16

youngwarlocks:
16 people

16C2= 120 (Combination)

75 pple

You can get it using factorials so the answer is 5. 5x4x3x2x1=120

58