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ORIGINAL STUDY COMPANION PADIKAM CLASS 11 | COMMERCE / HUMANITIES Economics: Statistics and Introductory Microeconomics CBSE / NCERT core lessons | Academic year 2026-27 15 chapter lessons Quick explanations, core points, exam practice and chapter-specific notation in one consistent format. Padikam explanations are independently written. Official textbooks are used as the coverage map, chapter sequence and terminology reference. PADIKAM | CBSE NCERT CLASS 11 1

Contents 01 Statistics for Economics: Introduction 09 Consumer Equilibrium: Utility Approach 02 Collection of Data 10 Consumer Equilibrium: Indifference Curve and Budget 03 Organisation of Data 11 Demand and Elasticity 04 Presentation of Data 12 Production, Cost and Revenue 05 Measures of Central Tendency 13 Producer Equilibrium and Supply 06 Correlation 14 Perfect Competition and Price 07 Index Numbers Determination 08 Introduction to Microeconomics 15 Applications and Economics Project Study rhythm Read the quick explanation, recall the core points aloud, then answer the prompts without looking back. Use the official textbook links for full prescribed readings, activities and diagrams. Textbook and verification links

1. https://cbseacademic.nic.in/web_material/CurriculumMain27/SecPart2/Economics_SecP2_2026-27.pdf
2. https://ncert.nic.in/textbook.php?kest1=0-7
3. https://ncert.nic.in/textbook.php?kecm1=0-6 PADIKAM | CBSE NCERT CLASS 11 2

CHAPTER 01 Statistics for Economics: Introduction Quick understanding Use statistics to organise economic facts, reveal patterns and support reasoned decisions while recognising limits. Core points Check your learning Statistics may mean numerical data or the methods State two uses and two limitations of used to collect and analyse them. statistics. Economic evidence needs context, definitions and Classify a statement as quantitative or comparable units. qualitative evidence. An average or graph supports judgement but cannot replace theory, ethics or local knowledge. One-line recall Statistics may mean numerical data or the methods used to collect and analyse them. PADIKAM | CBSE NCERT CLASS 11 3

CHAPTER 02 Collection of Data Quick understanding Choose primary or secondary data and a census or sample method that fits the question, population, time and resources. Core points Check your learning Primary data are collected for the present enquiry; Design five questions for a household secondary data already exist. survey. A census studies every population unit; a sample Compare census and sample methods studies a representative subset. for a large study. Question wording, non-response and selection can introduce bias. One-line recall Primary data are collected for the present enquiry; secondary data already exist. PADIKAM | CBSE NCERT CLASS 11 4

CHAPTER 03 Organisation of Data Quick understanding Turn raw observations into arrays, variables and frequency distributions without hiding important variation. Core points Check your learning A variable may be discrete or continuous. Construct a grouped frequency distribution. Exclusive classes suit continuous data; inclusive classes may need adjustment before analysis. Convert an inclusive distribution to continuous form. Class limits, boundaries, midpoint and width must remain consistent. Equation and notation Class mark xᵢ = (lower limit + upper limit) / 2 SYMBOLS AND UNITS xᵢ: midpoint of class i, in the data unit One-line recall A variable may be discrete or continuous. PADIKAM | CBSE NCERT CLASS 11 5

CHAPTER 04 Presentation of Data Quick understanding Select textual, tabular or diagrammatic forms that communicate comparison, composition, distribution and time change honestly. Core points Check your learning Tables need a number, title, headings, units, source Choose a suitable presentation for three and notes where required. data sets. Bar diagrams compare categories; histograms Identify a misleading scale and redraw it represent continuous frequency distributions. fairly. Arithmetic line graphs show movement over time. One-line recall Tables need a number, title, headings, units, source and notes where required. PADIKAM | CBSE NCERT CLASS 11 6

CHAPTER 05 Measures of Central Tendency Quick understanding Calculate and interpret arithmetic mean, median and mode, choosing the measure that suits the distribution and purpose. Core points Check your learning Mean uses every observation but is affected by Calculate all three measures for a small extremes. series. Median is positional and useful for skewed data or Justify the best average for household open-ended classes. income. Mode identifies the most frequent or typical value. Equation and notation x̄ = Σx / N Grouped mean x̄ = Σfᵢxᵢ / Σfᵢ Median = l + [(N/2 - c.f.)/f]h SYMBOLS AND UNITS x̄: arithmetic mean, in the data unit fᵢ: frequency of class i xᵢ: observation or class mark N: total frequency l: lower boundary of median class h: class width One-line recall Mean uses every observation but is affected by extremes. PADIKAM | CBSE NCERT CLASS 11 7

CHAPTER 06 Correlation Quick understanding Describe how two variables move together and calculate the direction and degree of association without claiming automatic causation. Core points Check your learning Positive and negative correlation refer to direction. Interpret three scatter patterns. A scatter diagram reveals broad form and outliers. Calculate a simple rank correlation. Correlation can arise from direct relation, reverse influence, common cause or coincidence. Equation and notation Spearman rₛ = 1 - 6Σd² / [n(n² - 1)] SYMBOLS AND UNITS rₛ: rank-correlation coefficient, dimensionless d: difference between paired ranks n: number of pairs One-line recall Positive and negative correlation refer to direction. PADIKAM | CBSE NCERT CLASS 11 8

CHAPTER 07 Index Numbers Quick understanding Use index numbers to compare a variable or basket across time and understand the role of base year, weights and item selection. Core points Check your learning An index expresses relative change with a base Calculate a simple aggregative price commonly set to 100. index. A weighted index reflects unequal importance of Explain how a poor base year can items. mislead. Consumer price indices support cost-of-living analysis but depend on the chosen basket and weights. Equation and notation Price relative = (P₁/P₀) × 100 Simple aggregative index = (ΣP₁/ΣP₀) × 100 SYMBOLS AND UNITS P₀: base-period price P₁: current-period price Index number: dimensionless One-line recall An index expresses relative change with a base commonly set to 100. PADIKAM | CBSE NCERT CLASS 11 9

CHAPTER 08 Introduction to Microeconomics Quick understanding Study how consumers and producers make choices under scarcity and how markets coordinate those choices. Core points Check your learning Positive economics explains what is; normative Explain one opportunity cost from daily economics judges what ought to be. life. An economy answers what, how and for whom to Interpret points on, inside and outside a produce. PPF. A production possibility frontier shows trade-offs, efficiency and opportunity cost. One-line recall Positive economics explains what is; normative economics judges what ought to be. PADIKAM | CBSE NCERT CLASS 11 10

CHAPTER 09 Consumer Equilibrium: Utility Approach Quick understanding Find the bundle that gives the greatest satisfaction within income and prices using marginal reasoning. Core points Check your learning Total utility is overall satisfaction; marginal utility is Complete a total and marginal utility the change from one more unit. table. Diminishing marginal utility helps explain downward- Find equilibrium for two goods from sloping willingness to pay. given data. At equilibrium, utility per rupee is balanced across goods under the stated assumptions. Equation and notation MU = ΔTU/ΔQ MUₓ/Pₓ = MUᵧ/Pᵧ, with full income spent SYMBOLS AND UNITS TU: total utility, hypothetical utility units MU: marginal utility Pₓ, Pᵧ: prices in currency per unit Q: quantity One-line recall Total utility is overall satisfaction; marginal utility is the change from one more unit. PADIKAM | CBSE NCERT CLASS 11 11

CHAPTER 10 Consumer Equilibrium: Indifference Curve and Budget Quick understanding Combine preferences and purchasing power to locate the highest attainable indifference curve. Core points Check your learning An indifference curve joins bundles giving equal Explain why indifference curves do not satisfaction. cross. A budget line contains affordable bundles that Find budget-line intercepts from income exhaust income. and prices. Equilibrium occurs where the budget line is tangent to a suitable convex indifference curve. Equation and notation Pₓx + Pᵧy = M At equilibrium: MRSₓᵧ = Pₓ/Pᵧ SYMBOLS AND UNITS x, y: quantities of goods M: consumer income in currency MRSₓᵧ: marginal rate of substitution, dimensionless One-line recall An indifference curve joins bundles giving equal satisfaction. PADIKAM | CBSE NCERT CLASS 11 12

CHAPTER 11 Demand and Elasticity Quick understanding Relate quantity demanded to own price and other determinants, distinguish movement from shift, and measure responsiveness. Core points Check your learning A movement along a demand curve follows an own- Separate movement and shift in four price change. cases. Income, tastes, related-goods prices and Calculate price elasticity by percentage expectations can shift demand. or expenditure method. Elasticity compares percentage changes and has no unit. Equation and notation e_d = percentage change in quantity demanded / percentage change in price SYMBOLS AND UNITS e_d: price elasticity of demand, dimensionless One-line recall A movement along a demand curve follows an own-price change. PADIKAM | CBSE NCERT CLASS 11 13

CHAPTER 12 Production, Cost and Revenue Quick understanding Connect inputs and output in the short run, then distinguish physical product, cost and revenue measures. Core points Check your learning With one variable input, marginal product eventually Calculate TP, AP and MP from a table. falls under the law of variable proportions. Construct TC, AC, AVC and MC columns. Fixed cost does not change with output in the short run; variable cost does. Marginal values measure the change caused by one additional unit. Equation and notation AP = TP/L MP = ΔTP/ΔL TC = TFC + TVC AC = TC/Q MC = ΔTC/ΔQ TR = P×Q; MR = ΔTR/ΔQ SYMBOLS AND UNITS TP: total product L: variable labour input TC, TFC, TVC: costs in currency Q: output quantity P: price per unit TR, MR: revenue measures in currency One-line recall With one variable input, marginal product eventually falls under the law of variable proportions. PADIKAM | CBSE NCERT CLASS 11 14

CHAPTER 13 Producer Equilibrium and Supply Quick understanding Find profit-maximising output and explain how own price and other determinants affect supply. Core points Check your learning A producer compares marginal revenue with Find equilibrium output from MR and MC marginal cost. schedules. Equilibrium requires MR = MC with MC rising through Distinguish movement along supply from MR. a shift. Technology, input prices, taxes, expectations and number of firms can shift supply. Equation and notation Profit = TR - TC Producer equilibrium: MR = MC SYMBOLS AND UNITS Profit, TR, TC: currency amounts MR, MC: currency per additional unit One-line recall A producer compares marginal revenue with marginal cost. PADIKAM | CBSE NCERT CLASS 11 15

CHAPTER 14 Perfect Competition and Price Determination Quick understanding Explain how market demand and supply determine equilibrium when many price-taking buyers and sellers interact. Core points Check your learning A perfectly competitive firm accepts the market price. Find equilibrium price from schedules. Excess demand pushes price upward; excess supply Analyse a demand or supply shift with a pushes it downward. labelled diagram. A simultaneous change in demand and supply may leave price or quantity ambiguous without relative magnitudes. Equation and notation Market equilibrium: Q_d = Q_s SYMBOLS AND UNITS Q_d: market quantity demanded Q_s: market quantity supplied One-line recall A perfectly competitive firm accepts the market price. PADIKAM | CBSE NCERT CLASS 11 16

CHAPTER 15 Applications and Economics Project Quick understanding Apply demand-supply reasoning and statistical enquiry to a focused economic question using transparent evidence. Core points Check your learning Price ceilings and floors can create shortage or Design a project on prices, employment, surplus when binding. consumption or public services. A project needs a question, method, evidence, Evaluate one government intervention analysis, conclusion, limitations and source list. using a demand-supply diagram. Protect privacy, avoid fabricated data and distinguish observation from opinion. One-line recall Price ceilings and floors can create shortage or surplus when binding. PADIKAM | CBSE NCERT CLASS 11 17