estimate
ok, so that would be the cost per unit
that is cost divided by the socks
one way is we could say 12 socks is close to 10 socks so
5.79/10=0.579 so about $0.58 per sock
or, we could round 5.79 ro 5.8
then
5.8/12=2.9/6=1.45/3≈0.39
so about 40 cents per sock
