Derangement | Formula Proof and Practice Questions (Permutations and Combinations) скачать в хорошем качестве

Derangement | Formula Proof and Practice Questions (Permutations and Combinations)

Derangement or De-arrangement is an important concept in Permutations and Combinations. This video lesson illustrates the concept and covers its proof through recursion using the classic-hat check scenario: Find the number of ways in which n hats can be returned to n people, such that no hat makes it back to its owner. The following actual questions from previous papers have additionally been discussed to make the application of Derangement crystal clear. Drop in any comments/queries regarding this topic in the comments box below. Question 1: A professor gave a test to 4 students – A, B, C, and D – and wants to let them grade each other's tests. How many ways could the professor hand the tests back to the students for grading, such that no student received their own test back? Question 2: If we place 6 letters into 6 addressed envelopes, what’s the probability that exactly 2 of them will be placed correctly? Link to our other lessons in the Permutations and Combinations Playlist:    • Permutations & Combinations   Access Previous Year papers & many other resources at www.ipmleap.com If you have any career specific query, pls feel free to comment below or contact us on any of the platforms below: Email: [email protected] Facebook: www.facebook.com/ipmleap Instagram: www.instagram.com/ipmleap Wish you a super duper successful career!! #IIM INDORE IPM #IPMAT 2021 #IPM IIM INDORE #JIPMAT #IPM_IIM_INDORE #IPM_IIM_ROHTAK #IPM_IIM_RANCHI #IPM_IIM_JAMMU #IPM_IIM_BODHGAYA #IPM_NIRMA_UNIVERSITY