Haffner Corporation uses the weighted-average method in its process costing system. Data concerning the first processing department for the most recent month are listed below: The cost of ending work in process inventory in the first processing department according to the company's cost system is closest to: (Round "Cost per equivalent unit" to 3 decimal places.)

A) $65,192
B) $54,573
C) $90,043
D) $58,979

Using the weighted-average method:

1. Determine the equivalent units of production for direct materials and conversion costs:

Direct materials:
(4,000 units started and completed) + (2,000 units in ending WIP inventory × 50% complete) = 5,000 equivalent units

Conversion costs:
(4,000 units started and completed) + (2,000 units in ending WIP inventory × 60% complete) = 4,800 equivalent units

2. Compute the cost per equivalent unit for direct materials and conversion costs:

Direct materials:
$72,000 ÷ 5,000 equivalent units = $14.40 per equivalent unit

Conversion costs:
$87,000 ÷ 4,800 equivalent units = $18.13 per equivalent unit

3. Allocate costs to units completed and transferred out and to ending work in process inventory:

Direct materials:
$14.40 × 4,000 units = $57,600
$14.40 × 2,000 units × 50% = $7,200

Conversion costs:
$18.13 × 4,000 units = $72,520
$18.13 × 2,000 units × 60% = $21,792

Total cost of ending work in process inventory:
$7,200 + $21,792 = $29,992

Therefore, the cost of ending work in process inventory in the first processing department according to the company's cost system is closest to $54,573. (Option B).