00:00:13 Fundamental Principle of Counting

00:07:33 NCERT Exercise 7.1 Question 1

How many 3-digit numbers can be formed from the digits 1, 2, 3, 4 and 5 assuming that (i) repetition of the digits is allowed? (ii) repetition of the digits is not allowed?

00:14:43 NCERT Exercise 7.1 Question 2

How many 3-digit even numbers can be formed from the digits 1, 2, 3, 4, 5, 6 if the digits can be repeated?

00:19:03 NCERT Exercise 7.1 Question 3

How many 4-letter code can be formed using the first 10 letters of the English alphabet, if no letter can be repeated?

00:22:02 NCERT Exercise 7.1 Question 4

How many 5-digit telephone numbers can be constructed using the digits 0 to 9 if each number starts with 67 and no digit appears more than once?

00:27:21 NCERT Exercise 7.1 Question 5

A coin is tossed 3 times and the outcomes are recorded. How many possible outcomes are there?

00:29:51 NCERT Exercise 7.1 Question 6

Given 5 flags of different colours, how many different signals can be generated if each signal requires the use of 2 flags, one below the other?

00:33:11 Factorial of a number

00:37:01 NCERT Exercise 7.2 Question 1

00:39:41 NCERT Exercise 7.2 Question 2

00:40:51 NCERT Exercise 7.2 Question 3

00:42:11 NCERT Exercise 7.2 Question 4

00:44:21 NCERT Exercise 7.2 Question 5