The company calculates a plant wide overhead rate by dividing total direct labor hours in total overhead costs. Plant overhead is a fixed cost during the year, but that direct labor is a variable cost.

Total plant overhead costs is $122,000 per year

Direct labor rate is $30 per hour

Production Volume - Units - 10,000

Selling Price - $15.00

Materials per unit - $4.00

Direct labor hours per unit - 0.24

Total direct labor hours - 2,400

How do you calculate the plant-wide cost driver rate and use this rate to assign overhead costs to products. Calculate the gross margin for each product and calculate the total gross margin.