Both the median and mean=27 so median or mean would work.
K, so areitmetic
an=a1+d(n-1)
a1=first term
d=common differnce
we are given
a1=2 and 3/4
6th term is 3 and 7/12
so
a6=3 and 7/12=2 and 3/4+d(6-1)
3 and 7/12=2 and 3/4+d(5)
minus 2 and 3/4 both sides
10/12=5d
divide both sides by 5 or multiply both sides by 1/5
2/12=d
1/6=d

or

that is the rule
Answer:
1.92 or 4.56 answer when rounded to 100th
2x2x1= 4 possible ways
GBP & BPP & BB
GBP & RPP & BB
YBP & BPP & BB
YBP & RPP & BB
GBP is green backpack, YBP is yellow backpack, BPP is blue pencil pouch, RPP is red pencil point, BB is black binder.