State the example of price and price level

Create a basket which contains all the goods sold by a specific store on a specific day. Price of this basket is then a price level - it would be a weighted average of prices of the goods sold that day and weights would be equal to number of every good sold. Perhaps basket contains 100 liters of regular milk though only one frozen cake. Price of regular milk will then have a weight of 100 whereas price of frozen cake wold have a weight of 1. Changes in price of milk will then have a greater influence on price level than changes in price of frozen cake.