math word problem help please?

Question

You have 9 mutual friends whom you would like to invite to dinner, 3 at a time, over the course of a dozen mini dinner parties. How can you arrange the invitations so that any pair of friends meet each other at dinner only once? Your friends are Alice, Brenda, Charlie, Daniel, Emily, Frank, George, Hanna, and Isabel.

thank you!

Answer 1

Favorite Answer

alice=a

brenda=b

charlie=c

daniel=d

emily=e

frank=f

george=g

hanna=h

isabel=i

these are the arrangements:

(1) ABC

(2) DEF

(3) GHI

(4) ADG

(5) BEH

(6) CFI

(7) AEI

(8) CEG

(9) AFH

(10) BDI

(11) CDH

(12) BGF

Answer 2

abc

ade

afg

ahi

bif

beg

bhd

cdf

ceh

cig

dgh

feh