Mary's Landscaping uses a job order cost system. The following debits (credits) appeared in Work-in-Process Inventory for August:

Description Amount
August 1 Balance $13,900
For the month Direct materials 81,100
For the month Direct labor 54,900
For the month Factory overhead 41,175
For the month To finished goods (160,300)

Mary's applies overhead to production at a predetermined rate of 81 percent based on direct labor cost. Job 3318, which was started during August and is the only job still in process at the end of August, has been charged direct labor of $6,400.

Required:
What cost amount of direct materials was charged to Job 3318?