Dressmaker medium

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Dressmaker database: medium questions

Assuming that any garment could be made in any of the available materials, list the garments (description, fabric, colour and pattern) which are expensive to make, that is, those for which the labour costs are 80% or more of the total cost.

List the descriptions and the number of orders of the less popular garments, that is those for which less than the average number of orders per garment have been placed. Also print out the average number of orders per garment. When calculating the average, ignore any garments for which no orders have been made.

Which is the most popular line, that is, the garment with the highest number of orders. Bearing in mind the fact that there may be several such garments, list the garment description(s) and number(s) of orders.

List the descriptions, and costs of the more expensive size 8, Cotton garments which might be ordered, that is those costing more than the average (labour costs + material costs) to make.

What is the most common size ordered for each garment type? List description, size and number of orders, assuming that there could be several equally popular sizes for each type.