Theory of the Firm under Perfect Competition Class 12 Economics PYQ

Class 12 Economics Theory of the Firm under Perfect Competition PYQ, free to download as a 73-page PDF. The chapter comes from the Microeconomics part of the older board pattern, and the set holds 99 solved questions from the 2005 to 2019 papers on the features of perfect competition, the price taker firm, total, average and marginal revenue and how they relate, producer's equilibrium, supply and its determinants, change in supply versus change in quantity supplied, and price elasticity of supply with its numericals and geometric method, and takes roughly seven hours to work through, so do the 17 one-mark and 29 three-mark questions in the first sitting, the 20 four-mark questions in the second, and the 33 six-mark questions over the last two.

Theory of the Firm under Perfect Competition Weightage in the Class 12 Board Paper

As per Economics Theory of the Firm under Perfect Competition weightage from past years, this chapter sat in the Microeconomics part of the older Class 12 paper, which shared the theory marks with Macroeconomics. The Class 12 Economics paper now listed for 2026-27 pairs Introductory Macroeconomics with Indian Economic Development, so it has no Microeconomics part, and we have not found an official chapter-wise mark figure for the old pattern. Use this set to practise the concepts and for school tests that still follow the Micro book, not as a forecast of this year's board paper.

The 99 questions in this set fall in four groups. 33 are 6-mark long answers, 29 are 3-mark short answers, 20 are 4-mark questions and 17 are 1-mark questions. That leaves 82 questions that need a written answer of three marks or more.

Theory of the Firm under Perfect Competition Questions by Topic

The features of perfect competition lead the set, with 22 questions. Of these, 7 are on the large number of buyers and sellers, 5 on homogeneous products, 4 on freedom of entry and exit and 2 on perfect knowledge, while 4 ask for the main features together. 5 questions ask why a firm is a price taker and not a price maker, and 3 more ask you to agree or disagree with a statement about the firm and the industry.

Revenue is in 30 questions: total revenue in 8, average revenue in 16 and marginal revenue in 21, since many questions use two or three of them. 5 ask for the relation of marginal revenue with total revenue or with average revenue, and 5 ask why average revenue equals price or why its curve is parallel to the X-axis.

Producer's equilibrium appears in 17 questions. 8 use the marginal cost and marginal revenue approach, including 4 that give a cost and revenue table and ask for the equilibrium output, and 2 that ask for the conditions through a numerical example. Supply is in 34 questions. 17 ask for a determinant or a cause of a shift, covering technology, input prices, a per unit tax, a subsidy and the prices of other goods. 9 ask to separate a change in supply from a change in quantity supplied, and 6 of the 99 questions ask for a diagram.

Price elasticity of supply is in 7 questions, and 4 of them are numericals where a percentage change in price or quantity has to be found. 1 question asks for the geometric method on a straight line supply curve. 3 questions are true or false with reasons. The counts come from keyword matches, so a question on two topics is counted under both.

Perfect Competition Video Lesson

Source: Next Toppers - 11th Commerce on YouTube

How to Approach the Theory of the Firm under Perfect Competition Set

Start with the 17 one-mark questions, about 17 minutes of fill in the blank and choose the correct alternative questions on the shape of the AR curve, MR parallel to the X-axis and elasticity of 3. Then take the 29 three-mark questions, which mostly ask for the implication of one feature or one determinant of supply.

In the 4-mark group, do the 4 elasticity numericals first, because each is a two-line calculation once the formula is written. Keep the 6-mark questions for later sittings. The producer's equilibrium answers need the table of marginal cost and marginal revenue or a diagram with both curves, and the feature answers need a reason for each feature, not just its name.

Common Mistakes in Theory of the Firm under Perfect Competition Questions

• Saying the industry is a price taker. The firm takes the price; the industry, through market demand and supply, sets it.
• Claiming average revenue equals marginal revenue in every market. That holds only when the price is the same at every output, as under perfect competition.
• Stopping at MR = MC. Marginal cost must also be rising beyond that output, or the firm is not in equilibrium.
• Drawing a downward movement along the supply curve as a leftward shift. A fall in price changes quantity supplied; a shift needs a change in something other than price.
• Showing a tax and a subsidy as shifting the curve the same way. A tax lowers supply, a subsidy raises it.
• Reversing the direction in an elasticity numerical. When price falls, supply falls by the percentage the elasticity gives.

Using the Answer Key and Solutions

The PDF is 73 pages and free to download. Questions are grouped by marks, each links to its worked solution and back, and the Answer Key lists the MCQ answers at a glance. Attempt a group first, check the key, then read the solution. The solutions are written by Collegedunia's Economics experts and are not official CBSE marking schemes.

Class 12 Economics PYQs by Chapter