The monthly per capita expenditure incurred by workers of an industrial centre during 1980 and 2005

The monthly per capita expenditure incurred by workers of an industrial centre during 1980 and 2005 on the following items are given below. The weights of these items are 75, 10, 5, 6, and 4, respectively. Prepare a weighted index number for cost of living for 2005 with 1980 as base.

Construction of Consumer Price Index