Section 1 : CH 0 Some preliminaries

Lecture 1 The prerequisites Introduction 0:53
Lecture 2 How to 'add' numbers 4:16
Lecture 3 How to 'subtract' numbers 3:13
Lecture 4 How to 'multiply' numbers 7:9
Lecture 5 Multiplying by 10, 100, 1000, 5:54
Lecture 6 How to 'divide' numbers 10:15
Lecture 7 The division algorithm 5:20
Lecture 8 Multiple of divisor nearest to the dividend 4:56
Lecture 9 Divisibility tests of numbers 8:39
Lecture 10 How to do 'cancellations' in division 6:35
Lecture 11 The 'VBODMAS' rule 6:27
Lecture 12 Problem session On 'VBODMAS' 10:13

Section 2 : CH 1 The Basics Number, Numeral and Numeration

Lecture 13 'Number' vs 'Numeral' vs 'Numeration' 12:23
Lecture 14 Numbers 7:57
Lecture 15 Numerals 11:55
Lecture 16 Roman Numeral System Introduction 4:9
Lecture 17 Roman Numeral System Rule 1 6:32
Lecture 18 Roman Numeral System Rule 2 4:7
Lecture 19 Roman Numeral System Rule 3 5:40
Lecture 20 Roman Numeral System Rule 4 9:55
Lecture 21 Roman Numeral System All 4 rules 10:46
Lecture 22 Problem session On 4 rules 3:42
Lecture 23 Roman Numeral System - 1 to 1000 14:1
Lecture 24 Roman Numeral System - 1001 to 3999 17:55
Lecture 25 Problem session Hindu-Arabic to Roman 9:40
Lecture 26 Roman Numeral System Roman to Hindu-Arabic 8:50
Lecture 27 Problem session Roman to Hindu-Arabic 20:3
Lecture 28 Roman Numeral System - beyond 3999 16:5
Lecture 29 Roman Numeral System Demerits 6:33
Lecture 30 Hindu-Arabic Numeral System 7:44
Lecture 31 Numeration 4:1
Lecture 32 International system of numeration 18:9
Lecture 33 Problem session International system of numeration 16:51
Lecture 34 Indian system of numeration 16:25
Lecture 35 Problem session Indian system of numeration 19:32
Lecture 36 International numeration and Indian numeration 5:12
Lecture 37 Conversion problems 17:13
Lecture 38 Difference between International numeration and Indian numeration 4:22

Section 3 : CH 1 The Basics 'Face value' and 'Place value'

Lecture 39 Face value and Place value 18:21
Lecture 40 Difference between 'Face value' and 'Place value' 2:32
Lecture 41 Problem session 1 16:7
Lecture 42 Problem session 2 11:23
Lecture 43 Problem session 3 15:8

Section 4 : CH 1 The Basics 'Expanded Form' of a Number

Lecture 44 Expanded form of a number Introduction 5:47
Lecture 45 Problem session Writing expanded form 12:43
Lecture 46 Problem session Writing number from expanded form 5:43

Section 5 : CH 1 The Basics Comparing Numbers

Lecture 47 Comparing 2 numbers Introduction 8:40
Lecture 48 Comparing 2 numbers Rule 1 6:22
Lecture 49 Problem session Rule 1 20:58
Lecture 50 Comparing 2 numbers Rule 2 2:44
Lecture 51 Problem session Rule 2 18:3
Lecture 52 Comparing 2 numbers Rule 3 8:5
Lecture 53 Problem session Rule 3 20:39
Lecture 54 Comparing 2 numbers Rule 4 5:26
Lecture 55 Problem session Rule 4 14:56
Lecture 56 Ascending order (Increasing order) 7:37
Lecture 57 Descending order (Decreasing order) 6:24
Lecture 58 Difference Ascending order vs Descending order 5:31
Lecture 59 Comparing more than 2 numbers Rules 7:29
Lecture 60 Comparing more than 2 numbers Example 1 9:4
Lecture 61 Comparing more than 2 numbers Example 2 17:4
Lecture 62 Comparing more than 2 numbers Example 3 11:55
Lecture 63 Problem session Ascending order and Descending order 25:54
Lecture 64 Problem session Finding the smallest number 5:22
Lecture 65 Problem session Finding the largest number 3:26

Section 6 : CH 1 The Basics Formation of Numbers

Lecture 66 Formation of Numbers - 1 6:2
Lecture 67 Formation of Numbers - 2 19:5
Lecture 68 Formation of Numbers - 3 17:18
Lecture 69 Formation of Numbers - 4 25:5
Lecture 70 Problem session - 1 17:44
Lecture 71 Problem session - 2 15:35
Lecture 72 Problem session - 3 14:4
Lecture 73 Problem session - 4 6:45
Lecture 74 Formation of Numbers - 5 14:39
Lecture 75 Formation of Numbers - 6 9:9
Lecture 76 Problem session - 5 16:36
Lecture 77 Problem session - 6 19:37
Lecture 78 Problem session - 7 14:9
Lecture 79 Problem session - 8 19:50
Lecture 80 Problem session - 9 15:6
Lecture 81 Problem session - 10 10:38

Section 7 : CH 1 The Basics Forming the greatest and the smallest number

Lecture 82 Forming the greatest and the smallest numbers with the given digits 20:30
Lecture 83 Problem session - 1 6:54
Lecture 84 Problem session - 2 8:58

Section 8 : CH 1 The Basics The smallest and the greatest numbers of n-digits

Lecture 85 The smallest and the greatest numbers of n-digits 14:37
Lecture 86 Problem session - 1 5:1
Lecture 87 Problem session - 2 4:46
Lecture 88 Some patterns 4:28

Section 9 : CH 1 The Basics Rounding off

Lecture 89 Rounding off - Introduction 9:48
Lecture 90 Rule - Rounding off to nearest tens 9:37
Lecture 91 Examples - Rounding off to nearest tens 11:35
Lecture 92 Problem session - Rounding off to nearest tens 14:3
Lecture 93 Rule - Rounding off to nearest hundreds 8:1
Lecture 94 Examples - Rounding off to nearest hundreds 8:26
Lecture 95 Problem session - Rounding off to nearest hundreds 16:22
Lecture 96 Rule - Rounding off to nearest thousands 7:56
Lecture 97 Examples - Rounding off to nearest thousands 5:55
Lecture 98 Problem session - Rounding off to nearest thousands 15:16
Lecture 99 Problem session - Rounding off 19:4
Lecture 100 Rounding off to nearest ten-thousands and further 8:24

Section 10 : CH 1 The Basics Estimation

Lecture 101 Estimation - Introduction 9:27
Lecture 102 Understanding estimation - Example 8:58
Lecture 103 Understanding estimation - Examples 9:23
Lecture 104 Uderstanding estimation - Examples 14:53
Lecture 105 Estimation - Theoritical points 20:34
Lecture 106 Understanding estimation - Example 4:34
Lecture 107 Understanding estimation - Example 3:33
Lecture 108 General rule of estimation 2:27
Lecture 109 Problem session - 1 7:35
Lecture 110 Problem session - 2 2:36
Lecture 111 Problem session - 3 2:47
Lecture 112 'Estimation in lower places' vs 'Estimation in higher places' 4:24

Section 11 : CH 2 Factors and Multiples

Lecture 113 What is a 'Product' 3:13
Lecture 114 What is a 'Factor' 8:7
Lecture 115 What is a 'Multiple' 4:20
Lecture 116 Properties of 'Factors' 11:49
Lecture 117 Properties of 'Multiples' 6:11
Lecture 118 How to find 'Factors' 5:42
Lecture 119 Problem session - Finding 'Factors' 21:23
Lecture 120 How to find 'Multiples' 1:15
Lecture 121 Problem session - Finding 'Multiples' 10:46
Lecture 122 What are 'Common factors' 9:43
Lecture 123 Problem session - Finding 'Common factors' 13:48
Lecture 124 What are 'Common multiples' 4:22
Lecture 125 Problem session - Finding 'Common multiples' 14:6
Lecture 126 Insight on 'Prime numbers' and 'composite numbers' 10:33
Lecture 127 What are 'Prime numbers' 4:28
Lecture 128 What are 'Composite numbers' 3:57
Lecture 129 Which number is 'Neither prime nor composite' 0:54
Lecture 130 Which number is 'Both prime and composite' 0:57
Lecture 131 What is 'Sieve of Eratosthenes' 15:47
Lecture 132 Steps to write 'Sieve of Eratosthenes' 5:46
Lecture 133 Problem session - Based on 'Sieve of Eratosthenes' 13:4
Lecture 134 Problem session - Testing primality of a number between 1 and 100 10:25
Lecture 135 Properties of Prime numbers 18:39
Lecture 136 Problem session - Properties of Prime numbers 6:26
Lecture 137 Test of Prime 9:17
Lecture 138 Problem session - Test of Prime 11:42
Lecture 139 Problem session - Test of Prime 9:19
Lecture 140 Proof of 'Primality test for numbers upto 100' 2:1
Lecture 141 Problem session - Test of Prime 1:17
Lecture 142 Problem session - Test of Prime 1:16
Lecture 143 What is 'Factorisation' 9:6
Lecture 144 What is 'Prime factorisation' 6:13
Lecture 145 'Factorisation' vs 'Prime factorisation' 3:40
Lecture 146 Fundamental theorem of Arithmetic 3:14
Lecture 147 How to find 'Prime factorisation' 5:25
Lecture 148 Problem session - Finding Prime factorisation 19:42
Lecture 149 Problem session - Prime factorisation 1:19
Lecture 150 Problem session - Prime factorisation 1:37
Lecture 151 Problem session - Prime factorisation 2:41
Lecture 152 Problem session - Prime factorisation 5:37
Lecture 153 Problem session - Prime factorisation 2:7
Lecture 154 Problem session - Prime factorisation 1:5
Lecture 155 Problem session - Prime factorisation 2:19
Lecture 156 Importance of 'Prime factors' and 'Prime factorisation' 2:6
Lecture 157 What is 'HCF' 8:3
Lecture 158 Different names of HCF 2:27
Lecture 159 HCF of two numbers - Method 1 2:16
Lecture 160 HCF of two numbers - Method 2 1:47
Lecture 161 HCF of two numbers - Method 3 1:35
Lecture 162 HCF of two numbers - Method 4 3:55
Lecture 163 HCF of two numbers - Method 5 1:30
Lecture 164 HCF of two numbers - Method 6 1:36
Lecture 165 HCF of two numbers - Method 7 3:10
Lecture 166 HCF of two numbers - Method 8 1:56
Lecture 167 HCF of two numbers - All 8 methods 6:39
Lecture 168 HCF of more than two numbers - Method 1
Lecture 169 HCF of more than two numbers - Method 2 2:14
Lecture 170 HCF of more than two numbers - Method 3 1:38
Lecture 171 HCF of more than two numbers - Method 4 2:34
Lecture 172 HCF of more than two numbers - Method 5 1:26
Lecture 173 HCF of more than two numbers - Method 6 1:35
Lecture 174 HCF of more than two numbers - Method 7
Lecture 175 Problem session - Finding HCF 23:5
Lecture 176 What is 'LCM' 11:0
Lecture 177 LCM of two numbers - Method 1 1:47
Lecture 178 LCM of two numbers - Method 2 4:4
Lecture 179 LCM of two numbers - Method 3 4:38
Lecture 180 LCM of two numbers - Method 4 1:56
Lecture 181 LCM of two numbers - Method 5 3:8
Lecture 182 LCM of two numbers - Method 6 1:45
Lecture 183 LCM of two numbers - Method 7 2:1
Lecture 184 LCM of two numbers - All 6 methods 6:44
Lecture 185 LCM of more than two numbers - Method 1 5:49
Lecture 186 LCM of more than two numbers - Method 2 2:33
Lecture 187 LCM of more than two numbers - Method 3 2:43
Lecture 188 LCM of more than two numbers - Method 4 2:50
Lecture 189 LCM of more than two numbers - Method 5 2:3
Lecture 190 LCM of more than two numbers - Method 6 1:48
Lecture 191 Problem session - Finding LCM 22:35
Lecture 192 Problem session - HCF vs LCM 17:33
Lecture 193 What are 'Coprime numbers' 3:46
Lecture 194 What are 'Twin-primes' 1:16
Lecture 195 What is a 'Perfect number' 2:46
Lecture 196 What is a 'Prime-triplet' 1:27
Lecture 197 What are 'Even numbers' and 'Odd numbers' 4:37
Lecture 198 Properties of HCF and LCM 15:53
Lecture 199 Problem session - Properties of HCF and LCM 3:21
Lecture 200 Relation between HCF, LCM and product of two numbers 11:51
Lecture 201 Problem session - Relation between HCF, LCM and product of two numbers 6:14
Lecture 202 HCF word problems - Introduction 11:51
Lecture 203 Problem session - Word problems on HCF 19:5
Lecture 204 Problem session - Word problems on HCF 16:55
Lecture 205 Problem session - Word problems on HCF 22:22
Lecture 206 LCM word problems - Introduction 5:5
Lecture 207 Problem session - Word problems on LCM 12:51
Lecture 208 Problem session - Word problems on LCM 12:23
Lecture 209 Problem session - Word problems on LCM 10:26
Lecture 210 Problem session - Problems on HCF and LCM 15:54
Lecture 211 Problem session - Problems on HCF and LCM 15:15
Lecture 212 Problem session - Problems on HCF and LCM 10:14
Lecture 213 Problem session - Word problems on HCF and LCM 13:1
Lecture 214 Problem session - Word problems on HCF and LCM 13:38
Lecture 215 Problem session - Word problems on HCF and LCM 9:50

Section 12 : CH 3 Rules of Divisibility

Lecture 216 First rule of divisibility 4:25
Lecture 217 Problem session 0:51
Lecture 218 Second rule of divisibility 2:27
Lecture 219 Problem session 1:14
Lecture 220 Third rule of divisibility 1:10
Lecture 221 Problem session 1:5
Lecture 222 Problem session 5:18
Lecture 223 Problem session 3:31
Lecture 224 Fourth rule of divisibility 2:41

Section 13 : CH 4 Divisibility Tests (with proofs)

Lecture 225 What is 'Divisibility test' 2:8
Lecture 226 Division by 0 1:7
Lecture 227 Divisibility test of 1 0:41
Lecture 228 Divisibility test of 2 2:36
Lecture 229 Problem session - Divisibility test of 2 1:21
Lecture 230 Proof of 'divisibility test of 2' 3:30
Lecture 231 Divisibility test of 3 3:10
Lecture 232 Problem session - Divisibility test of 3 3:17
Lecture 233 Proof of 'divisibility test of 3' 4:52
Lecture 234 Divisibility test of 4 2:13
Lecture 235 Problem session - Divisibility test of 4 2:56
Lecture 236 Proof of 'divisibility test of 4' 3:6
Lecture 237 Divisibility test of 5 1:17
Lecture 238 Problem session - Divisibility test of 5 0:55
Lecture 239 Proof of 'divisibility test of 5' 2:30
Lecture 240 Divisibility test of 6 2:20
Lecture 241 Problem session - Divisibility test of 6 3:19
Lecture 242 Proof of 'divisibility test of 6' 1:7
Lecture 243 Divisibility test of 7 10:28
Lecture 244 Problem session - Divisibility test of 7 2:34
Lecture 245 Proof of 'divisibility test of 7' 9:38
Lecture 246 Divisibility test of 8 1:16
Lecture 247 Problem session - Divisibility test of 8 3:22
Lecture 248 Proof of 'divisibility test of 8' 1:31
Lecture 249 Divisibility test of 9 2:55
Lecture 250 Problem session - Divisibility test of 9 2:51
Lecture 251 Proof of 'divisibility test of 9' 1:41
Lecture 252 Divisibility test of 10 0:34
Lecture 253 Problem session - Divisibility test of 10 0:53
Lecture 254 Proof of 'divisibility test of 10' 2:16
Lecture 255 Divisibility test of 11 13:21
Lecture 256 Problem session - Divisibility test of 11 7:49
Lecture 257 Proof of 'divisibility test of 11' 11:9
Lecture 258 Divisibility test of 12 2:48
Lecture 259 Proof of 'divisibility test of 12' 1:11
Lecture 260 Divisibility test of 13 2:37
Lecture 261 Proof of 'divisibility test of 13' 4:30
Lecture 262 Divisibility test of 14 3:1
Lecture 263 Proof of 'divisibility test of 14' 0:57
Lecture 264 Divisibility test of 15 2:8
Lecture 265 Proof of 'divisibility test of 15' 0:59
Lecture 266 Coprime factors test 4:20
Lecture 267 Revision of divisibility tests of natural numbers upto 15 5:19
Lecture 268 Problem session - Divisibility tests upto 15 2:19

Section 14 : CH 5 Number System The various number systems

Lecture 269 Number System - Introduction 9:3
Lecture 270 Natural numbers 20:8
Lecture 271 Problem session - Natural numbers 7:6
Lecture 272 Whole numbers - Part 1 24:34
Lecture 273 Whole numbers - Part 2 10:10
Lecture 274 Problem session - Whole numbers 6:14
Lecture 275 Integers - Part 1 22:46
Lecture 276 Integers - Part 2 24:37
Lecture 277 Problem session - Integers 2:27
Lecture 278 Problem session - Integers 4:42
Lecture 279 Problem session - Integers on number line 3:57
Lecture 280 Fractions - Part 1 17:56
Lecture 281 Fractions - Part 2 19:10
Lecture 282 Fractions - Part 3 16:38
Lecture 283 Fractions - Part 4 21:34
Lecture 284 Fractions - Part 5 11:31
Lecture 285 Fractions - Part 6 16:42
Lecture 286 Fractions - Part 7 16:2
Lecture 287 Fractions - Part 8 9:43
Lecture 288 Fractions - Part 9 21:34
Lecture 289 Problem session - Fractions 3:8
Lecture 290 Problem session - Fractions 2:9
Lecture 291 Problem session - Fractions (shading) 3:25
Lecture 292 Problem session - Fractions (shading) 2 1:6
Lecture 293 Problem session - Fractions (proper, improper, mixed) 2:52
Lecture 294 Problem session - Fractions (simplest form) 4:17
Lecture 295 Problem session - Fractions (equivalent fractions) 4:46
Lecture 296 Problem session - Fractions (like and unlike) 3:2
Lecture 297 Problem session - Fractions (plotting) 6:0
Lecture 298 Problem session - Fractions (word problems) 4:37
Lecture 299 Rational numbers - Part 1 15:42
Lecture 300 Rational numbers - Part 2 12:19
Lecture 301 Rational numbers - Part 3 3:39
Lecture 302 Rational numbers - Part 4 7:38
Lecture 303 Rational numbers - Part 5 2:26
Lecture 304 Rational numbers - Part 6 2:57
Lecture 305 Rational numbers - Part 7 4:5
Lecture 306 Rational numbers - Part 8 2:51
Lecture 307 Rational numbers - Part 9 1:25
Lecture 308 Rational numbers - Part 10 19:55
Lecture 309 Rational numbers - Part 11 25:24
Lecture 310 Rational numbers - Part 12 10:40
Lecture 311 Rational numbers - Part 13 9:33
Lecture 312 Rational numbers - Part 14 5:35
Lecture 313 Rational numbers - Part 15 3:56
Lecture 314 Rational numbers - Part 16 1:37
Lecture 315 Rational numbers - Part 17 26:0
Lecture 316 Rational numbers - Part 18 10:53
Lecture 317 Rational numbers - Part 19 9:16
Lecture 318 Rational numbers - Part 20 17:42
Lecture 319 Problem session - Rational numbers 3:17
Lecture 320 Problem session - Rational numbers 1 3:14
Lecture 321 Problem session - Rational numbers 2 5:38
Lecture 322 Problem session - Rational numbers 3 3:20
Lecture 323 Problem session - Rational numbers 4 2:56
Lecture 324 Recap of Number systems - Part 1 13:34
Lecture 325 Recap of Number systems - Part 2 10:23
Lecture 326 God made Integers, rest are man-made 5:13

Section 15 : CH 5Number System Comparison and ordering of numbers of various number systems

Lecture 327 Comparison and Ordering of Numbers - Introduction 1:23
Lecture 328 Comparison of Natural numbers - Introduction 4:24
Lecture 329 Comparison of Natural numbers - Method 1 7:51
Lecture 330 Comparison of Natural numbers - Method 2 6:38
Lecture 331 Comparison of Natural numbers - Method 3 13:25
Lecture 332 Comparison of Natural numbers - All 3 methods 4:44
Lecture 333 Ordering of Natural numbers 3:49
Lecture 334 Comparison of Whole numbers - Introduction 3:7
Lecture 335 Comparison of Whole numbers - Method 1 4:40
Lecture 336 Comparison of Whole numbers - Method 2 3:42
Lecture 337 Comparison of Whole numbers - Method 3 8:1
Lecture 338 Comparison of Whole numbers - All 3 methods 3:43
Lecture 339 Ordering of Whole numbers 3:20
Lecture 340 Comparison of Integers - Introduction 3:47
Lecture 341 Absolute value or modulus of an Integer 19:2
Lecture 342 Problem session - Plotting Integers 2:16
Lecture 343 Comparison of Integers - Method 1 16:44
Lecture 344 Comparison of Integers - Method 2 12:28
Lecture 345 Comparison of Integers - Method 3 11:13
Lecture 346 Comparison of Integers - All 3 methods 5:55
Lecture 347 Ordering of Integers 3:52
Lecture 348 Problem session - Comparison of integers 2:22
Lecture 349 Problem session - Comparison of Integers 4:34
Lecture 350 Comparison of Fractions - Introduction 9:33
Lecture 351 Comparison of Fractions - Method 1 7:56
Lecture 352 Comparison of Fractions - Method 2 10:51
Lecture 353 Comparison of Fractions - Method 3 11:5
Lecture 354 Comparison of Fractions - Method 4 5:5
Lecture 355 Comparison of Fractions (Mixed fractions) - Method 5 10:16
Lecture 356 Comparison of Fractions - Method 6 7:24
Lecture 357 Comparison of Fractions - Method 7 5:51
Lecture 358 Comparison of Fractions - Method 8
Lecture 359 Comparison of Fractions - All 8 methods 10:37
Lecture 360 Ordering of Fractions 5:43
Lecture 361 Problem session - Comparison of fractions 4:17
Lecture 362 Comparison of Rational numbers - Introduction 4:54
Lecture 363 Comparison of Rational numbers - Method 1 10:39
Lecture 364 Comparison of Rational numbers - Method 2 16:50
Lecture 365 Comparison of Rational numbers - Method 3 5:39
Lecture 366 Comparison of Rational numbers - All 7 methods 12:57
Lecture 367 Ordering of Rational numbers 4:51
Lecture 368 Problem session - Comparison of rational numbers 4:42

Section 16 : CH 5 Number System Fundamental operations on numbers of various number systems

Lecture 369 Fundamental operations on numbers - Introduction 5:34
Lecture 370 How to add, subtract, multiply and divide two natural numbers 11:40
Lecture 371 Operations on natural numbers through number line 19:58
Lecture 372 How to add, subtract, multiply and divide two whole numbers 5:37
Lecture 373 Operations on Whole numbers through number line 11:36
Lecture 374 Absolute value of an Integer 3:47
Lecture 375 How to add two integers 19:29
Lecture 376 How to add two or more integers 27:33
Lecture 377 Problem session - Addition of integers 7:27
Lecture 378 How to multiply two integers 14:47
Lecture 379 How to multiply two or more integers 12:0
Lecture 380 Important points in multiplication of integers 17:4
Lecture 381 Problem session - Multiplication of integers 3:25
Lecture 382 Problem session - Additive inverse of integers 2:47
Lecture 383 How to subtract two integers 5:42
Lecture 384 A useful tip in addition and subtraction of two integers 5:22
Lecture 385 Easier ways of subtracting integers 12:32
Lecture 386 How to subtract two or more integers 6:21
Lecture 387 Problem session - Subtraction of integers 6:59
Lecture 388 Problem session - Addition and subtraction of integers 5:19
Lecture 389 Problem session - Successor and predecessor of integers 3:19
Lecture 390 How to divide two integers 13:44
Lecture 391 How to divide two or more integers 7:22
Lecture 392 Problem session - Division of integers 3:9
Lecture 393 Problem session - Simplification of integers 8:36
Lecture 394 How to add two fractions 18:5
Lecture 395 How to add two or more fractions 9:47
Lecture 396 Problem session - Addition of fractions 2:45
Lecture 397 How to subtract two fractions 11:49
Lecture 398 How to subtract two or more fractions 3:13
Lecture 399 Problem session - Subtraction of fractions 4:5
Lecture 400 How to multiply two fractions 7:4
Lecture 401 How to multiply two or more fractions 9:26
Lecture 402 Problem session - Multiplication of fractions 3:25
Lecture 403 How to divide two fractions 6:40
Lecture 404 How to divide two fractions - An important point 7:52
Lecture 405 How to divide two or more fractions 9:57
Lecture 406 Problem session - Division of fractions 4:7
Lecture 407 All operations on two fractions 5:31
Lecture 408 Problem session - Simplification of fractions 6:57
Lecture 409 How to add two rational numbers 12:2
Lecture 410 How to add two or more rational numbers 8:50
Lecture 411 Problem session - Addition of rational numbers 5:15
Lecture 412 How to subtract two rational numbers 10:48
Lecture 413 How to subtract two or more rational numbers 7:39
Lecture 414 Problem session - Subtraction of rational numbers 7:9
Lecture 415 How to multiply two rational numbers 6:9
Lecture 416 How to multiply two or more rational numbers 7:11
Lecture 417 Problem session - Multiplication of rational numbers 2:51
Lecture 418 How to divide two rational numbers 9:27
Lecture 419 How to divide two or more rational numbers 8:28
Lecture 420 Problem session - Division of rational numbers 2:59
Lecture 421 All operations on two rational numbers 6:47

Section 17 : CH 5 Number System Properties of numbers of various number systems

Lecture 422 Closure Property - Introduction 11:1
Lecture 423 Closure property for Natural numbers 15:14
Lecture 424 Closure property for Whole numbers 10:43
Lecture 425 Closure property for Integers 10:15
Lecture 426 Closure property for Fractions 14:37
Lecture 427 Closure property for Rational numbers 10:55
Lecture 428 Summary of Closure property 10:25
Lecture 429 Commutative Property - Introduction 6:31
Lecture 430 Commutative property for Natural numbers 7:7
Lecture 431 Commutative property for Whole numbers 6:9
Lecture 432 Commutative property for Integers 6:29
Lecture 433 Commutative property for Fractions 9:38
Lecture 434 Commutative property for Rational numbers 10:24
Lecture 435 Summary of Commutative property 14:12
Lecture 436 Associative Property - Introduction 5:41
Lecture 437 Associative property for Natural numbers 11:26
Lecture 438 Associative property for Whole numbers 10:1
Lecture 439 Associative property for Integers 9:28
Lecture 440 Associative property for Fractions 16:15
Lecture 441 Associative property for Rational numbers 12:57
Lecture 442 Summary of Associative property 9:59
Lecture 443 Distributive Property - Introduction 13:15
Lecture 444 Distributive property for Natural numbers 5:42
Lecture 445 Distributive property for Whole numbers 4:9
Lecture 446 Distributive property for Integers 4:18
Lecture 447 Distributive property for Fractions 10:40
Lecture 448 Distributive property for Rational numbers 12:31
Lecture 449 Summary of Distributive property 14:53
Lecture 450 Why do we multiply the way we multiply 13:2
Lecture 451 Additive Identity and Multiplicative Identity - Introduction 6:31
Lecture 452 Additive Identity and Multiplicative Identity for Natural numbers 4:30
Lecture 453 Additive Identity and Multiplicative Identity for Whole number 2:43
Lecture 454 Additive Identity and Multiplicative Identity for Integers 2:44
Lecture 455 Additive Identity and Multiplicative Identity for Fractions 3:22
Lecture 456 Additive Identity and Multiplicative Identity for Rational Numbers 3:25
Lecture 457 Summary of Additive Identity and Multiplicative Identity 2:59
Lecture 458 Multiplication and Division by ZERO (0) 3:5

Section 18 : CH 6 Decimal Numbers

Lecture 459 Revision of 'Integers' 4:42
Lecture 460 Integral powers of 10 5:2
Lecture 461 Understanding numbers 8:12
Lecture 462 'Place values' and 'Place value table' 4:32
Lecture 463 'Place value table' and 'Integral powers of 10' 3:38
Lecture 464 Extension of 'Place value table' towards right of ones place 5:56
Lecture 465 Expansion of numbers written in place value table 3:32
Lecture 466 Obtaining a number written in place value table 3:6
Lecture 467 Introducing the 'Decimal point' 5:33
Lecture 468 Obtaining a number written in place value table 5:48