oppositeemotions
oppositeemotions oppositeemotions
  • 10-11-2017
  • Mathematics
contestada

At a party, everyone shook hands with everyone else. There were 66 handshakes. How many people were at the party? Explain.

Respuesta :

dannielle
dannielle dannielle
  • 17-11-2017
n-the number of people
The first person shake n-1 hands, the second n-2....the last person shake one hand

1+2+3+.....+n-1=n*(n-1)/2=66
⇒ n*(n-1)=66*2=132=12*11
⇒ n=12 people was at the party
Answer Link

Otras preguntas

Name three arthropod head appendages and their functions
What did Karl Marx believe was the solution to the injustice and inequality of the bourgeoisie's exploitation of the proletarians regarding the means of product
What did Karl Marx believe was the solution to the injustice and inequality of the bourgeoisie's exploitation of the proletarians regarding the means of product
how many times does 6 go into 30
The price of a Panasonic 3D flat screen television decreased by 1∕5. If the original price was $1,500, what is the price today?
Enzymes are proteins that speed up reactions by
members of congress represent their districts by doing what?
log 9 (729) = ?, I know what logarithims are but dont quite understand this one
What does Frederick Taylor mean by maximum prosperity?
The circumference of a circle is two times pi(p) times the radius. Translate the sentence into a formula