What do you understand by “product mix”? What are all the advantages of a good "Product Mix"?

A range of associated products that yields larger sales revenue when marketed together than if they were marketed individually or in isolation from others.

Product mix or assortment is a group of products which are available through one company and it is totally different than product system which are group of integrative products which is better to be sold as bundle

ex: I pod, head phone, cable, case

the product mix include four main parameters which are the key for any sucessful company 

1- product width: how many product line

2- product length: how many products in every line

3- product depth: how many forms from each product

consistency: how close these products are especially in manufacturing, classification , distribution and so on

The product mix is the complete range of products &/or services offered by a company therefore it is also known as product portfolio. Product-mix may contain a single or multiple set of related products or services.

A good product-mix will ensure satisfying the needs of many customers in a segment and thus would help the company to increase its customerbase in a competitive market and thereby grow long term sales, revenue and market share. However, the number of products or the width and depth of products line depend on substantial market need, company resources and segmental strategy.

just wanted to add on above answers 

Product mix is advantageous , as each product is having a have different life cycle  , where in one product can be under the maturity state and another product is currently undergoing yielding stage ,

so once a product gets  into the exit state another product go into maturity stage, and long term vision is met with 

Diversified product lines.

Group of products in the portfolio of a company which contribute to sales of company and generate optimum revenue it may be a product basket of assorted products.

Its a strategy to link the new product with the successful one. In other words, it is the strategy to link the one product with another as an essential part to raise the number of customers for each product.

The product is the basic instrument of marketing mix in organizations engaged in manufacturing.It is  the assortment of merchandise made or held for sale. Some companies have a wide product mix geared toward a diverse consumer group. The product is one of the marketing mix through which a company harmonize its capabilities with the needs and requirements of the customer / consumer. It occurs as a result of the efforts of all employees in the company to meet the demands and needs of the market.

Snezana Brankovic 

Product mix is a range of products which can cater to requirements of different segments of the market. It is beneficial in targeting wide market potential; ease and cost effective in production due to high level of product similarity; ease and cost effective in maintenance due to high level of similarity in spare parts and consumables; 

agreed with all ,,,,,

Good Day!!!

I believe Mr. Fady Zeid has given the most comprehensive answer. Appreciated