In some instances accounting principles require a departure from valuing inventories at cost alone. Determine the proper unit inventory price in the following cases.
Cases
1 2 3 4 5
Cost $15.90 $16.10 $15.90 $15.90 $15.90
Sales price 14.80 19.20 15.20 10.40 17.80
Estimated cost to complete 1.50 1.90 1.65 .80 1.00
Estimated cost to sell .50 .70 .55 .40 .60