Spratley Ltd is a builders merchant. On 1 September the business had, as part of its inventories, 20 tonnes of sand at a cost of 18 per tonne and, therefore, at a total cost of 360. During the first week in September, the business bought the following amounts of sand:

	Tonnes	Cost per tonne
2 September	48	20
4 September	15	24
6 September	10	25

On 7 September the business sold 60 tonnes of sand to a local builder.

Required:

Calculate the cost of goods sold and of the remaining inventories using the following costing methods:

1. first in, first out

2. last in, first out

3. weighted average cost.