if P and C is a problem to you , and u are looking forward to do probability and some maths. then i think i have an easy way and the most efficient also. and finally plz don't read this if u already have done it. "I already know everyone is a genius " still i have written it so it may help someone. as the time is short this can be used to cover a lot in just 4 hours.
this requires 4 hours only and u will be surely be satisfied after this. remember follow step by step.
In pnc every question feels like that it is a new type of question and when we apply our logic we always get different answer. There is a shortcut. go to youtube.com, search for pnc . there will be 2 lectures from a female lecturer of iit i think kamla something. just put the video speed to 1.5 or 2 and then u can easily see the videos in 1-2 hours. Just skip the proves if u want, and try to focus on the cases we have, proof is not requires . just write all the cases she told like. n distinct cells and n cells.
here are the links. https://www.youtube.com/watch?v=Dsi7x-A89Mw and the next one. 29. two lectures of 1 hours. but they actually have a material of 20 min only.
Now try solving some of the question like here i am posting some of the links of questions u can do try applying the cases to the problem .
https://gateoverflow.in/28749/combinatorics?show=28749#viewbutton
https://gateoverflow.in/28302/combinatory?show=28302#q28302
try solving these . u will get the basic of pnc till now. now the second type of question which they may ask is . the word problems. for that u have to go to any of the apptitude book and cover them. just do one question and u will be covering all the cases.
here is such one question
http://math.stackexchange.com/questions/709437/permutation-and-combination-problem-word-arrangement
till now u have covered the basic and the word problems. now move on to some of the hard problems which u may get on probability as they are closely related.
the most hard problems are of dearrangement. go here and u can get a innerview of it.
https://www.youtube.com/watch?v=jjycA-1S1_8
here u can see a lot of cases . now these problem will be easy to solve .
http://math.stackexchange.com/questions/922473/n-people-n-hats-probability-that-at-least-1-person-has-his-own-hat
https://www.quora.com/At-a-party-n-men-take-off-their-hats-The-hats-are-then-mixed-up-and-each-man-randomly-selects-one-We-say-that-a-match-occurs-if-a-man-selects-his-own-hat-What-is-the-probability-of-no-matches-What-about-exactly-k-matches
so you have done a lot of questions till now. just try to remember the pattern of problem. these are all the tools. just identify which tool you have to use,
here is a special type of question that looks like p n c but actually a function question and should always kept in mind. because they does not ask a direct formula based question on onto functions
https://gateoverflow.in/29329/entrepreneur-assign-different-tasks-employees-should-atleast#viewbutton.
congo u have cleared a lot of things . just make notes of notes . and from now on you will be able to solve a lot of questions. and now on just give every pnc a try.
and keep revising. If this helped u kindly upvote. so that more people can use this . Thnks
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