math
posted by Katie on .
Three students from grades 10,11 and 12 were elected to the student council.
Grade 10: Tom(T), Sally(s) and Bill(B)
Grade 11: Jerry(J),Anne(A)and Connie(C)
Grade 12: Dan(D), Martha(M) and Gwen(G)
A three member committee is to be formed with one person from each grade. All possible combinations must be considered before a decision is made. Two possible combinatons are Tom, Jerry, and Dan (TJD) and Sally, Anne, and Martha (SAM). List all other possible combinations for the committee.

there are 27 such combinations.
Do you actually expect somebody to list those for you?
go about it systematically:
TJD
TJM
TJG
etc 
tjd, tjm, tjg, tad, tam, tag, tcd, tcm, tcg, sjd, sjm, sjg, sad, sam, sag, scd, scm, scg, bjd, bjm, bjg, bad, bam, bag, bcd, bcm ,bcg

Ayeeeeeeeeeeee