Step 1 :Calculate the total revenue for B300: \(60000 \times 19 = 1140000\)
Step 2 :Calculate the total direct labor cost for B300: \(60000 \times 8 = 480000\)
Step 3 :Calculate the total direct material cost for B300: \(60000 \times 5 = 300000\)
Step 4 :Calculate the total overhead cost for B300: \(60000 \times 1.6 \times 8 = 768000\)
Step 5 :Calculate the product margin for B300: \(1140000 - 480000 - 300000 - 768000 = -408000\)
Step 6 :Calculate the total revenue for T500: \(12600 \times 40 = 504000\)
Step 7 :Calculate the total direct labor cost for T500: \(12600 \times 10 = 126000\)
Step 8 :Calculate the total direct material cost for T500: \(12600 \times 15 = 189000\)
Step 9 :Calculate the total overhead cost for T500: \(12600 \times 1.6 \times 10 = 201600\)
Step 10 :Calculate the product margin for T500: \(504000 - 126000 - 189000 - 201600 = -12600\)
Step 11 :\(\boxed{\text{Under the traditional costing system, the product margin for B300 is } -\$408,000 \text{ and for T500 is } -\$12,600}\)