How do companies that earn from production determine their prices?

Revenue should be more than the cost of production in order to make a profit.
Calculate how much it costs to make your product (including labor and materials) and look at how much competitors are charging. If your price is too much more than theirs, it’ll be hard to compete. Especially if your product is new on the market and hasn’t made a name for itself yet (meaning no one has seen what it’s capable of). If it’s lower than competitor pricing, your product will appeal to the buyers looking for a deal.

basically costs (wages, electricity, rents, raw materials, etc) divided by production number (which is determined by how much you expect to be able to sell) plus profit margin plus VAT. details may vary

Pricing has many many strategies, but the most common are skimming (you are the only producer of an in-demand commodity so you charge what you can get until competitors catch on) penetration, where you control a market the way Time Warner controls cable in NYC, economy, where you, like WalMart, undercut other suppliers to be more attractive; and premium pricing, where, like the Maybach, or Harry Winston Jewelers, you are seen as having greater cachet than your competitors.

As much as the buyer is willing to pay. If you’re to expensive no one will buy, and if you’re to cheap you won’t be able to produce it fast enough.
When I worked retail I had an old merchant tell me that there are two types of people in retail. merchants and operations people. Merchants want to buy enough product that when the season is over you have one left over. Operations people want to buy so much that you have one less than the number of buying customers.
Setting your prices is the same sort of thing. You want to set it so you maximize profit. You make money on volume and on mark-up.. The balancing act is to figure out what price point is the “perfect” combination of mark up and volume to create the most total income. Figuring that out is as much art as it is math, although some math whiz could probably write a matrix for just about any business.

You can find the theory in most textbooks of industrial management. However, there are some producers whose pricing and marketing decisions are hard to understand. In this class I include publishers; most of them seem to use magic or divination or some form of casting the bones.