Bus Driver Training. Nation$-$Wide Bus Lines is proud of its six$-$week bus driver$$training program that it conducts for all new Nation$-$Wide drivers.

As long as the class size remains less than or equal to $35,$ a six$-$week training program costs Nation$-$Wide

$

$22,000$

for instructors, equipment, and so on$.$ The Nation$-$Wide training program must provide the company with approximately five new drivers per month. After completing the training program, new drivers

are paid

$

$1600$

per month but do not work until a full$-$time driver position is open. Nation$-$Wide views the

$

$1600$

per month paid to each idle new driver as a holding cost necessary to maintain a supply of newly trained drivers available

for immediate service.

$($LO $1$LO $1$Recognize the sources of inventory costs in the economic order quantity $($EOQ$)$ model and appropriately apply the EOQ model

to make how$-$much$-$to$-$order and when$-$to$-$order decisions.$)$

Viewing new drivers as inventory$-$type units, how large should the training classes be to minimize Nation$-$Wide$$s total annual

training and new driver idle$-$time costs?