At an auto shop, six jobs are currently in queue.

$\backslash$table$[[$Job$,$A$,$B$,$C$,$D$,$E$,$F$],[$Arrival order,$1,2,3,4,5,6],[$Processing time $($minutes$),20,23,13,15,25,22]]$

Using the shortest processing time scheduling approach, what is the average inventory of jobs in the system? Assume that processing of jobs will start immediately.

Note: Round your answer to $2$ decimal places.

Average inventory

jobs