#### Section 1 : Algebra Introduction

 Lecture 1 Beginning of Algebra 0:51 Lecture 2 Where did the word 'Algebra' come from 2:16 Lecture 3 What is 'Algebra' 4:23 Lecture 4 'Arithmetic' vs 'Algebra' 4:38 Lecture 5 Who is an 'Algebraist' 0:55 Lecture 6 Indian name for 'Algebra' 1:59 Lecture 7 Usages of Algebra 3:40

#### Section 2 : Algebra Constants and Variables

 Lecture 8 Introduction 0:27 Lecture 9 Two types of numbers in Algebra 1:0 Lecture 10 What is a 'Constant' 1:59 Lecture 11 What is a 'Variable' 4:12 Lecture 12 What is a 'Literal' 1:19 Lecture 13 'Constant' vs 'Variable' 2:34 Lecture 14 Constants with 'unknown' values 3:41 Lecture 15 Fundamental operations on variables 2:17 Lecture 16 Why can we perform operations on variables 5:14 Lecture 17 Shorter way to write product of variables 10:51 Lecture 18 Repeated multiplication (or Exponentiation) of variables 8:5 Lecture 19 A variable to the power zero (0) 2:17 Lecture 20 Repeated addition (or Multiplication) of variables 4:36 Lecture 21 Properties of operations on variables 7:2

#### Section 3 : Algebra Algebraic Expressions

 Lecture 22 Algebraic expression - Introduction 0:23 Lecture 23 What is an 'Algebraic expression' 7:52 Lecture 24 'Arithmetic expression' vs Algebraic expression' 3:18 Lecture 25 What are 'terms' 7:9 Lecture 26 How to identify 'terms' in an algebraic expression 2:52 Lecture 27 'Constant term' in an algebraic expression 3:55 Lecture 28 'Factors' of a term 5:34 Lecture 29 Tree diagram 2:13 Lecture 30 'Numerical factor' and 'Variable factor' 3:32 Lecture 31 What are 'Coefficients' 12:0 Lecture 32 'Numerical coefficient' and 'Literal coefficient' 8:41 Lecture 33 What are 'Like terms' 8:18 Lecture 34 What are 'Unlike terms' 3:8 Lecture 35 How to add or subtract 'terms' 5:17 Lecture 36 How to add or subtract 'like terms' 9:1 Lecture 37 How to add or subtract 'Unlike terms' 5:36 Lecture 38 How to add or subtract 'Algebraic expressions' 13:54 Lecture 39 How to multiply 'terms' 3:56 Lecture 40 How to multiply two 'algebraic expressions' 6:50 Lecture 41 Finding the value of an algebraic expression 6:37

#### Section 4 : Algebra Polynomials

 Lecture 42 Polynomial - Introduction 0:38 Lecture 43 A variable to the power whole number 1:51 Lecture 44 (Constant) X (A variable to the power whole number) 7:9 Lecture 45 What is a 'Polynomial in 1 variable' 14:59 Lecture 46 What is a 'Constant polynomial' 3:5 Lecture 47 'Terms' of a polynomial 13:3 Lecture 48 'Coefficients' of terms of a polynomial 5:32 Lecture 49 'Degree' of a polynomial in 1 variable 12:7 Lecture 50 Summary of concepts 6:20 Lecture 51 Classification of polynomials 1:53 Lecture 52 What is a 'Linear polynomial' 10:25 Lecture 53 What is a 'Quadratic polynomial' 9:33 Lecture 54 What is a 'Cubic polynomial' 9:8 Lecture 55 'Constant polynomial' - Revisited 4:59 Lecture 56 Summary of polynomials based on 'degree' 7:52 Lecture 57 Degree table of polynomials 6:21 Lecture 58 Classifying polynomials on 'Number of terms' 6:25 Lecture 59 Polynomials in more than 1 variable 7:4

#### Section 5 : Algebra Linear equation in 1 variable

 Lecture 60 What are 'variables' and 'constants' 8:20 Lecture 61 What is an 'Expression' 5:39 Lecture 62 Problem session - variables, constants and expressions 1:29 Lecture 63 What is an 'Equation' 10:14 Lecture 64 Parts of an equation 18:24 Lecture 65 What is 'Equation in 1 variable' 8:45 Lecture 66 Problem session - On identifying equation in 1 variable 3:58 Lecture 67 Problem session - On identifying equation in 1 variable 3:17 Lecture 68 What is 'Linear equation in 1 variable' 7:58 Lecture 69 Problem session - Identifying 'Linear equation in 1 variable' 6:29 Lecture 70 'Solution' or 'root' of an equation - Part 1 8:23 Lecture 71 'Solution' or 'root' of an equation - part 2 11:19 Lecture 72 'Solution' or 'root' of an equation - part 3 0:47 Lecture 73 Number of roots of an equation 8:40 Lecture 74 Plotting the roots of an equation 2:47 Lecture 75 'Solution' or 'root' of a L 9:9 Lecture 76 Why is a Linear equation called 'Linear' 2:11 Lecture 77 Problem session - Understanding the meaning of solution 4:34 Lecture 78 Problem session - Understanding the meaning of solution 3:22 Lecture 79 Problem session - Understanding the meaning of solution 6:36 Lecture 80 What is 'Solving a L 1:42 Lecture 81 Two methods of solving LE1V 1:20 Lecture 82 Trial and Error method of solving L 9:31 Lecture 83 Problem session - Trial and Error method 9:37 Lecture 84 Problem session - Trial and Error method 9:4 Lecture 85 Demerits of Trial and Error method 2:7 Lecture 86 An equation as a weighing balance 4:29 Lecture 87 Properties of a balanced equation 13:11 Lecture 88 Gist of properties of balanced equation 6:59 Lecture 89 Systematic method of solving L 9:5 Lecture 90 Problem session - Systematic method - Part 1 11:11 Lecture 91 What is 'Transposition' 7:26 Lecture 92 Problem session - Systematic method - Part 2 7:19 Lecture 93 Problem session - Systematic method - Part 3 10:1 Lecture 94 Problem session - Systematic method - Part 4 9:2 Lecture 95 Problem session - Systematic method - Part 5 6:47 Lecture 96 Problem session - Systematic method - Part 6 10:15 Lecture 97 Problem session - Systematic method - Part 7 13:59 Lecture 98 Setting up an equation 4:49 Lecture 99 Problem session - Converting statements to equations 5:5 Lecture 100 Problem session - Setting up equations 7:11 Lecture 101 Problem session - Word problems 20:25 Lecture 102 Problem session - Word problems 18:9 Lecture 103 Problem session - Word problems 10:58 Lecture 104 Checking the solution 6:52 Lecture 105 Problem session - Checking the solution 6:53 Lecture 106 Plotting the solution of LE1V 2:58 Lecture 107 Problem session - Plotting solution of LE1V 7:44 Lecture 108 Standard form of a LE1V 6:55 Lecture 109 Problem session - Writing LE1V in standard form 6:3 Lecture 110 Problem session - Overall chapter in one session 11:47 Lecture 111 Revision of the chapter - Part 1 8:50 Lecture 112 Revision of the chapter - Part 2 4:26 Lecture 113 Revision of the chapter - Part 3 21:36 Lecture 114 Revision of the chapter - Part 4 6:24 Lecture 115 Revision of the chapter - Part 5 12:24 Lecture 116 Revision of the chapter - Part 6 13:0 Lecture 117 Revision of the chapter - Part 7 8:7

#### Section 6 : Plane Geometry Introduction

 Lecture 118 Break up of the word 'Geometry' 6:1 Lecture 119 What is 'Geometry' 3:50 Lecture 120 How did Geometry evolve 7:6 Lecture 121 2 Types of Geometries 3:24 Lecture 122 Which Geometry will we study 2:12 Lecture 123 Geometry of the Universe 0:56 Lecture 124 Who is the 'Father of Geometry' 1:22 Lecture 125 Who gave the 'first known proof' 1:45 Lecture 126 Who is a 'Geometer' 0:54

#### Section 7 : Plane Geometry Meaning of 'Axioms' & 'Theorems'

 Lecture 127 Two types of 'Statements' in Mathematics 1:38 Lecture 128 Axioms or Postulates 5:1 Lecture 129 Theorems or Propositions 3:6

#### Section 8 : Plane Geometry PLANE

 Lecture 130 What is a 'Plane' 4:25

#### Section 9 : Plane Geometry POINT

 Lecture 131 Definition of 'Point' 1:16 Lecture 132 Why is a 'Point' not defined in Geometry 7:28 Lecture 133 A Point is a 'Primitive Object' 2:50 Lecture 134 Characteristics of a Point 3:37 Lecture 135 How to represent a Point 4:55 Lecture 136 How to draw a Point on paper 1:55 Lecture 137 How to denote a Point 1:45 Lecture 138 Practical examples of a Point 1:42

#### Section 10 : Plane Geometry LINE SEGMENT

 Lecture 139 Definition of a Line-segment 3:6 Lecture 140 Definition of a Line-segment from a Line 3:18 Lecture 141 Another word for Line-segment 0:58 Lecture 142 How to denote a Line-segment 2:13 Lecture 143 'Line-segment AB' vs 'Line-segment BA' 1:2 Lecture 144 The length of a Line-segment 5:32 Lecture 145 Characteristics of a Line-segment 3:41 Lecture 146 How to compare lengths of Line-segments 10:49 Lecture 147 Practical examples of Line-segments 3:58

#### Section 11 : Plane Geometry LINE

 Lecture 148 Definition of 'Line' 0:54 Lecture 149 Why is a 'Line' not defined in Geometry 4:20 Lecture 150 Line is a 'Primitive Object' 1:42 Lecture 151 What is a 'Straight Line' 3:34 Lecture 152 Defining a line from a Line-segment Lecture 153 Defining a Line from 'Intersecting planes' 1:48 Lecture 154 Complete picture of a Line cannot be drawn 1:43 Lecture 155 How to denote a Line 1:46 Lecture 156 'Line AB' vs 'Line BA' 0:43 Lecture 157 Characteristics of a Line 3:25 Lecture 158 How many Lines can be drawn passing through 1 given point 1:8 Lecture 159 How many Lines can be drawn passing through 2 given points 0:54 Lecture 160 Two points fix a line 1:53 Lecture 161 What are Collinear points 3:6 Lecture 162 What are Non-collinear points 1:36 Lecture 163 What are Concurrent lines 2:55 Lecture 164 Practical examples of lines 2:36

#### Section 12 : Plane Geometry RAY

 Lecture 165 What is a 'Ray' 2:38 Lecture 166 Definition of a 'Ray' from a 'Line' 2:19 Lecture 167 Definition of a 'Ray' from a 'Line-segment' 2:30 Lecture 168 About the complete picture of a Ray 1:20 Lecture 169 How to denote a Ray 1:20 Lecture 170 Starting point of a Ray AB 1:12 Lecture 171 'Ray AB' vs 'Ray BA' 2:28 Lecture 172 Number of rays that can be drawn from a 'Starting point' 1:36 Lecture 173 Ray from 2 given points 2:13 Lecture 174 Characteristics of a ray 3:5 Lecture 175 Practical examples of rays 2:32

#### Section 13 : Plane Geometry 'LINE' vs 'LINE SEGMENT' vs 'RAY'

 Lecture 176 'Line' vs 'Line segment' vs 'Ray' 8:11

#### Section 14 : Plane Geometry ANGLE

 Lecture 177 Origin of the word 'Angle' 2:6 Lecture 178 What is an 'Angle' 8:51 Lecture 179 Symbol for Angle 0:52 Lecture 180 How to denote an angle 8:49 Lecture 181 What is the 'Measure of an angle' 2:21 Lecture 182 How to denote the 'Measure of an angle' 4:36 Lecture 183 What is 'One Complete Revolution' 3:38 Lecture 184 What is 'Complete angle' or 'Full angle' 2:6 Lecture 185 What is 'Straight angle' 2:37 Lecture 186 What is 'Right angle' 5:23 Lecture 187 'Three-fourth' of a revolution has no special name 4:37 Lecture 188 Relation among a 'Complete angle', a 'Straight angle' and a 'Right angle' 4:45 Lecture 189 Comparison among a 'Complete angle', a 'Straight angle' and a 'Right angle' 1:41 Lecture 190 Systems of measuring angle 1:42 Lecture 191 Centesimal system (French system) 8:6 Lecture 192 Sexagesimal system (English system) 11:2 Lecture 193 Circular system 2:49 Lecture 194 Degree measurement of a complete angle, a straight angle and a right angle 4:45 Lecture 195 Types of angles 13:21 Lecture 196 Examples of 7 types of angles 4:52 Lecture 197 Comparison among 7 types of angles 2:44 Lecture 198 Automatic formation of Reflex angle 2:23 Lecture 199 Distinction between an angle and its reflex counterpart 3:9 Lecture 200 Two important results 9:35 Lecture 201 How to compare angles 9:53 Lecture 202 Instrument to measure an angle 3:9 Lecture 203 An angle leads to 3 divisions of a region 9:12 Lecture 204 Practical examples of angles 2:58

#### Section 15 : Plane Geometry Pairs of Angles

 Lecture 205 Pairs of Angles 1:51 Lecture 206 Complementary angles 7:40 Lecture 207 Supplementary angles 7:38 Lecture 208 Adjacent angles 10:53 Lecture 209 Linear pair of angles 3:16 Lecture 210 Linear Pair Axiom 6:22 Lecture 211 Vertically opposite angles 2:58 Lecture 212 Theorem concerning 'Vertically opposite angles' 6:38 Lecture 213 'Linear pair axiom' vs 'Vertically opposite angles theorem' 3:34

#### Section 16 : Plane Geometry Pairs of Lines

 Lecture 214 Pairs of Lines - Introduction 1:9 Lecture 215 Parallel Lines 6:17 Lecture 216 Intersecting Lines 4:14 Lecture 217 Perpendicular Lines 9:46 Lecture 218 'Perpendicular bisector' of a line segment 11:1 Lecture 219 What are 'Transversals' 7:47 Lecture 220 Angles made by a transversal 4:31 Lecture 221 'Exterior Angles' made by a transversal 2:50 Lecture 222 'Interior Angles' made by a transversal 2:35 Lecture 223 Pairs of exterior angles on same side of transversal 2:49 Lecture 224 Pairs of interior angles on same side of transversal 3:6 Lecture 225 Pairs of corresponding angles formed by a transversal 6:36 Lecture 226 Pairs of Alternate interior angles formed by a transversal 5:2 Lecture 227 Pairs of Alternate exterior angles formed by a transversal 2:37 Lecture 228 Revision of all types of angles formed by transversal 7:52

#### Section 17 : Plane Geometry Parallel lines & a Transversal

 Lecture 229 Parallel lines and a transversal - Introduction 5:19 Lecture 230 Corresponding angles axiom 6:25 Lecture 231 Alternate angle theorem 4:49 Lecture 232 Proof of 'Alternate angle theorem' 4:58 Lecture 233 Theorem regarding interior angles on same side of transversal 4:0 Lecture 234 Proof of theorem regarding interior angles on same side of transversal 4:22 Lecture 235 Most important result (for competitions) 6:23

#### Section 18 : Plane Geometry CURVE

 Lecture 236 What is a 'Curve' 6:59 Lecture 237 Two types of curves 0:37 Lecture 238 What is 'Open curve' 1:47 Lecture 239 What is 'Closed curve' 3:4 Lecture 240 What is 'Simple curve' 2:2 Lecture 241 What is 'Simple Closed Curve' 3:36 Lecture 242 A 'Simple Closed Curve' leads to 3 divisions of a region 12:39

#### Section 19 : Plane Geometry POLYGON

 Lecture 243 What is a 'Polygon' 6:55 Lecture 244 What are 'Sides' or 'Edges' of a polygon 3:0 Lecture 245 What are 'Vertices' or 'Corners' of a polygon 3:31 Lecture 246 What are 'Adjacent sides' of a polygon 2:20 Lecture 247 What are 'Adjacent vertices' of a polygon 2:27 Lecture 248 What is 'Diagonal' of a polygon 8:41 Lecture 249 A polygon leads to 3 divisions of a region 4:16 Lecture 250 Angles in a polygon 16:23 Lecture 251 What are 'Adjacent angles' in a polygon 3:1 Lecture 252 Quick recapitulation 10:26 Lecture 253 Types of Polygons 0:42 Lecture 254 What is 'Convex polygon' 11:26 Lecture 255 What is 'Concave polygon' 10:57 Lecture 256 Names of some polygons 9:17 Lecture 257 Types of Convex polygon 0:52 Lecture 258 What is 'Regular polygon' 7:32 Lecture 259 What is 'Irregular polygon' 1:21

#### Section 20 : Plane Geometry TRIANGLE

 Lecture 260 What is a 'Triangle' 9:14 Lecture 261 How to denote a triangle 3:16 Lecture 262 'Interior', 'On' and 'Exterior' of a triangle 6:8 Lecture 263 'Sides' of a Triangle 2:14 Lecture 264 'Vertices' of a Triangle 2:8 Lecture 265 'Adjacent sides' of a Triangle 2:33 Lecture 266 'Adjacent vertices' of a Triangle 2:24 Lecture 267 Sides opposite to vertices 3:28 Lecture 268 Vertices opposite to sides 3:2 Lecture 269 Interior angles of a triangle 2:40 Lecture 270 Exterior angles of a triangle 5:29 Lecture 271 'Diagonals' of a triangle 1:15 Lecture 272 Elements in a triangle 6:38 Lecture 273 'Angle sum property' of a triangle 16:24 Lecture 274 'Exterior angle property' of a triangle 8:57 Lecture 275 Types of triangles 2:48 Lecture 276 Types of triangles based on 'sides' Lecture 277 Types of triangles based on 'angles' 10:50 Lecture 278 Inequalities in a triangle - Introduction 1:56 Lecture 279 Inequalities in a triangle - The 1st inequality 15:40 Lecture 280 Inequalities in a triangle - The 2nd inequality 15:5 Lecture 281 Inequalities in a triangle - 1st and 2nd inequalities 3:26 Lecture 282 Inequalities in a triangle - The 3rd inequality 4:24 Lecture 283 Inequalities in a triangle - The 4th inequality 5:48 Lecture 284 Bound on a side of a triangle 5:50 Lecture 285 Special lines and special line-segments in a triangle 2:31 Lecture 286 'Medians' in a triangle 15:49 Lecture 287 'Centroid' or 'Gravity centre' of a triangle 5:46 Lecture 288 'Altitudes' in a triangle 18:49 Lecture 289 'Orthocenter' of a triangle 5:52 Lecture 290 'Interior angle bisectors' in a triangle 16:18 Lecture 291 'Incentre' of a triangle 5:23 Lecture 292 'Side perpendicular bisectors' in a triangle 19:41 Lecture 293 'Circumcenter' of a triangle 8:16 Lecture 294 All 4 centres in a sample triangle 7:7 Lecture 295 Right-angled triangle 10:36 Lecture 296 Pythagoras theorem 2:51

#### Section 22 : Plane Geometry Circle

 Lecture 320 Introduction to Circle 3:43 Lecture 321 What is a 'Circle' 13:36 Lecture 322 A circle is a 'Simple closed curve' 2:37 Lecture 323 A circle leads to 3 divisions of a region 6:3 Lecture 324 What is 'Centre' of a circle 4:7 Lecture 325 What is 'Radius' of a circle 5:8 Lecture 326 Distance of a point from the centre of a circle 6:24 Lecture 327 What is 'Chord' of a circle 5:25 Lecture 328 What is 'Diameter' of a circle 6:22 Lecture 329 What is 'Arc' of a circle 10:18 Lecture 330 What is 'Circumference' of a circle 3:23 Lecture 331 What is 'Semi-circle' 3:42 Lecture 332 'Chord associated with an arc' and vice-versa 2:15 Lecture 333 What is 'Sector' 8:49 Lecture 334 Two types of quadrilaterals 10:9 Lecture 335 Differences in diagrams of 'Arc', 'Segment' and 'Sector' 3:32 Lecture 336 What is 'Semi-circular region' 3:8 Lecture 337 'Quadrant' of a circle 3:28 Lecture 338 Circles passing through 1 given point in a plane 2:22 Lecture 339 Circles passing through 2 given points in a plane 3:35 Lecture 340 Circle passing through 3 given points in a plane 10:39 Lecture 341 What are 'Concentric circles' and 'Annulus' 4:19 Lecture 342 What is a 'Cyclic quadrilateral' 2:18 Lecture 343 What is a 'Secant' 2:22 Lecture 344 'Chord associated with a secant' and vice-versa 3:0 Lecture 345 What is a 'Tangent' 15:29 Lecture 346 Number of tangents from a point to a circle 8:58 Lecture 347 Which Instrument is used to construct a circle 1:38

#### Section 23 : 3 Dimensional geometry

 Lecture 348 What is a 1D shape 3:5 Lecture 349 What is a 2D shape 4:10 Lecture 350 What is a 3D shape Lecture 351 Five 3D shapes that we will study 0:44 Lecture 352 What is a 'Cuboid' 7:23 Lecture 353 What is a 'Cube' 3:16 Lecture 354 What is a 'Cylinder' 3:49 Lecture 355 What is a 'Cone' 3:10 Lecture 356 What is a 'Sphere' 2:53 Lecture 357 Problem session - Mixed problems 3:37

#### Section 24 : Symmetry

 Lecture 358 Two types of symmetries 0:51 Lecture 359 What is 'mirror image' of an object 2:14 Lecture 360 How to draw 'mirror images' - Introduction 0:56 Lecture 361 How to draw mirror image of a 'point' 4:44 Lecture 362 Problem session - Mirror image of a 'point' 4:36 Lecture 363 How to draw mirror image of a 'plane figure' 5:23 Lecture 364 Problem session - Mirror image of a 'plane figure' 5:1 Lecture 365 What is 'Linear symmetry' 3:59 Lecture 366 Test of 'Linear symmetry' 3:19 Lecture 367 Problem session - Line of symmetry 4:11 Lecture 368 Problem session - Line of symmetry 2:27 Lecture 369 Problem session - Line of symmetry 1:59 Lecture 370 Problem session - Line of symmetry 2:8 Lecture 371 Line of symmetries of some standard figures 11:8 Lecture 372 Problem session - Line of symmetry 1:42 Lecture 373 Problem session - Line of symmetry 6:22 Lecture 374 Problem session - Line of symmetry 4:12 Lecture 375 Line of symmetries of English alphabets 2:11 Lecture 376 Problem session - Symmetries of Alphabets 4:57

#### Section 25 : Geometrical constructions

 Lecture 377 Introduction to 'Geometrical Constructions' 2:26 Lecture 378 Constructing a circle of given radius 1:56 Lecture 379 Previous construction on notebook 3:21 Lecture 380 Constructing a line segment of given length 2:57 Lecture 381 Previous construction on notebook 4:38 Lecture 382 Constructing a copy of a given line segment 1:51 Lecture 383 Previous construction on notebook 3:17 Lecture 384 Constructing the perpendicular bisector of a line segment 4:9 Lecture 385 Previous construction on notebook 8:56 Lecture 386 Constructing an equilateral triangle 1:46 Lecture 387 Previous construction on notebook 3:47 Lecture 388 Constructing a perpendicular to a line through a point on it 4:38 Lecture 389 Construction 7 on copy 9:32 Lecture 390 Constructing a perpendicular to a line through a point not on it 4:54 Lecture 391 Construction 8 on copy 7:21 Lecture 392 Constructing an angle using protractor 2:20 Lecture 393 Constructing an angle using protractor 2:53 Lecture 394 Constructing a copy of a given angle 2:53 Lecture 395 Constructing a copy of a given angle 4:44 Lecture 396 Constructing bisector of a given angle 3:0 Lecture 397 Constructing bisector of a given angle 4:11 Lecture 398 Constructing 60 deg, 120 deg, 180 deg and 90 deg 9:24 Lecture 399 Constructing 60 deg, 120 deg, 180 deg and 90 deg 6:30 Lecture 400 Constructing multiples of 15 degrees 9:50 Lecture 401 Constructing multiples of 15 degrees 11:56

#### Section 26 : Mensuration

 Lecture 402 What is 'Mensuration' 3:36 Lecture 403 What is 'perimeter' 5:34 Lecture 404 Problem session - Finding perimeter 4:36 Lecture 405 Perimeter of some standard figures Lecture 406 Problem session - Perimeter of rectangle 13:33 Lecture 407 Problem session - Perimeter or rectangle 10:19 Lecture 408 Problem session - Perimeter of square 11:57 Lecture 409 Problem session - Perimeter of miscellaneous shapes 9:11 Lecture 410 What is 'area' 2:39 Lecture 411 Area of rectangle and square 4:11 Lecture 412 Problem session - Rectangle and square 12:29 Lecture 413 Problem session - Square 12:33 Lecture 414 Problem session - Rectangle and square 11:59 Lecture 415 Problem session - Rectangle and square 9:54 Lecture 416 Circle - Circumference and area 7:42 Lecture 417 Problem session - Mensuration of circle 10:29 Lecture 418 Estimating area by counting squares 4:13 Lecture 419 Problem session - Estimating area by counting squares 2:57

#### Section 27 : Statistics

 Lecture 420 What is 'Data' 4:24 Lecture 421 The word 'statistics' 2:6 Lecture 422 Meaning of the word 'statistics' as plural noun 1:44 Lecture 423 Meaning of the word 'Statistics' as singular noun 2:7 Lecture 424 Definition of 'Statistics' 2:1 Lecture 425 Stages of statistical study 3:1 Lecture 426 Stage 1 - Collection of data 7:5 Lecture 427 Stage 2 - Organisation of data 2:58 Lecture 428 What is 'Array' 5:45 Lecture 429 What is 'Frequency distribution table' 13:18 Lecture 430 Problem session - Tally Marks 1:25 Lecture 431 'Array' vs 'Frequency distribution table' 10:15 Lecture 432 Problem session - 'Array' and 'Frequency distribution table' 9:29 Lecture 433 Problem session - Interconverting 'Array' and 'Freq dist table' 2:24 Lecture 434 Problem session - 'Tally Marks' and 'Frequency' 1:13 Lecture 435 Problem session - Frequency distribution table Lecture 436 Stage 3 - Presentation of data 2:33 Lecture 437 What is 'Pictograph' 9:39 Lecture 438 Problem session - Pictograph 1:15 Lecture 439 Problem session - Pictograph 6:10 Lecture 440 Problem session - Pictograph 11:47 Lecture 441 Demerits of 'Pictograph' 3:43 Lecture 442 What is 'Bar graph' 10:49 Lecture 443 Problem session - Bar graph 1 3:6 Lecture 444 Problem session - Bar graph 2 7:49 Lecture 445 Problem session - Bar graph 3 6:44 Lecture 446 Problem session - Bar graph 4 4:7 Lecture 447 Problem session - Bar graph 5 2:37 Lecture 448 Stages 4 and 5 - Analysis and interpretation of data 4:39 Lecture 449 What is 'Mean' 4:46 Lecture 450 How to calculate 'mean' 6:24 Lecture 451 What is 'Median' 18:27 Lecture 452 How to calculate 'median' 7:12 Lecture 453 What is 'Mode' 9:8 Lecture 454 How to calculate 'mode' 2:29 Lecture 455 What is 'Range' 3:8 Lecture 456 How to calculate 'range' 2:29 Lecture 457 Problem session - Mean, median, mode, range 6:23 Lecture 458 Problem session - Mean, median, mode, range 10:2 Lecture 459 Problem session - Mean, median, mode, range 6:11 Lecture 460 Problem session - Mean, median, mode, range 7:10 Lecture 461 Properties of mean, median and mode 4:47

#### Section 28 : Trigonometry Introduction

 Lecture 462 Trigonometry - Introduction 0:52 Lecture 463 Division of the word 'Trigonometry' 2:11 Lecture 464 What is 'Trigonometry' 5:8 Lecture 465 What will we study in 'Trigonometry' 2:28

#### Section 29 : Trigonometry The required background

 Lecture 466 The required background 0:40 Lecture 467 Basics of a right angled triangle 5:35 Lecture 468 How to identify 'sides' opposite to 'angles' in a triangle 6:44 Lecture 469 Problem session - Identifying 'sides' opposite to 'angles' 3:52 Lecture 470 How to identify 'hypotenuse' 3:22 Lecture 471 Problem session - Identifying the 'hypotenuse' 2:12 Lecture 472 Side adjacent to an acute angle in a right angled triangle 5:31 Lecture 473 Problem session - Mixed 4:6 Lecture 474 'Ratios of sides' in a right angled triangle 5:1 Lecture 475 Problem session - Writing all the 6 ratios of pairs of sides 6:34

#### Section 30 : Trigonometry Trigonometric ratios of acute angles

 Lecture 476 Introduction to Trigonometric ratios 4:47 Lecture 477 Glimpse to Trigonometric ratios 5:36 Lecture 478 Definition of Trigonometric ratios 9:45 Lecture 479 How to find the 'sine' of an acute angle of a right triangle 2:57 Lecture 480 Problem session - Finding 'sine' 5:4 Lecture 481 How to find the 'cosine' of an acute angle of a right triangle 2:45 Lecture 482 Problem session - Finding 'cosine' 3:12 Lecture 483 How to find the 'tangent' of an acute angle of a right triangle 2:58 Lecture 484 Problem session - Finding 'tangent' 2:38 Lecture 485 How to find the 'cosecant', 'secant' and 'cotangent' 5:22 Lecture 486 Problem session - Finding 'cosecant', 'secant', 'cotangent' 7:16 Lecture 487 Problem session - Finding all trigonometric ratios 3:43 Lecture 488 Problem session - Finding all trigonometric ratios 2:47

#### Section 31 : Coordinate Geometry

 Lecture 489 What is coordinate geometry 9:18 Lecture 490 Another name of coordinate geometry 1:22 Lecture 491 Problem session 1:10 Lecture 492 Who invented coordinate geometry 1:10 Lecture 493 What are 'Coordinate axes' 20:8 Lecture 494 What is 'x-axis' 8:11 Lecture 495 What is 'y-axis' 7:8 Lecture 496 Problem session - On coordinate axes 2:47 Lecture 497 What is 'Origin' 3:25 Lecture 498 What is 'coordinate plane' 8:14 Lecture 499 What are 'Quadrants' 8:14 Lecture 500 What is 'x-coordinate' or 'abscissa' of a point 16:45 Lecture 501 What is 'y-coordinate' or 'ordinate' of a point 12:57 Lecture 502 'Cartesian coordinates' of a point - Part 1 16:0 Lecture 503 'Cartesian coordinates' of a point - Part 2 17:14 Lecture 504 Summary of coordintates of a point 4:29 Lecture 505 Problem session - Writing and plotting coordinates 5:15 Lecture 506