3.5 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:

(a) first in, first out

(b) last in, first out

(c) weighted average cost.