Total manufacturing cost per unit is calculated by adding the conversion cost per unit to the manufacturing cost per unit.
Total material cost = $90,000
Unit produced = 10,000
Cost per unit = 90,000/10,000 = 9
A unit of the product cost $9
The cost per unit will be added to the conversion cost to get the total manufacturing cost
Total manufacturing cost = $9 + $ 6 = $15.
The total manufacturing cost per unit is $15.