Combinations and Permutations Combinations and Permutations


Combinations and PermutationsCombinations and Permutations



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Permutation and combination related questions are common in PSC and Bank exams.

Before going to Combinations and Permutations, first lean about factorial.

If \'n\' is a positive integer then, factorial of n is denoted as n!.


5! = ( 1 x 2 x 3 x 4 x 5 ) = 120

4! = (1 x 2 x 3 x 4 ) = 24


Permutations are for lists of items, whose order matters and combinations are for group of items where order doesn’t matter. in other words,

  • When the order of items doesn\'t matter, it is called as Combination.
  • When the order of items does matter it is called as Permutation.


The number of permutations of n objects taken r at a time is determined by using this formula:

P(n,r)=n!/(n−r)!

Permutation: Listing your 3 favourite football team in order, from list of 10 teams. P(10,3) = 720.


The number of combinations of n objects taken r at a time is determined by using this formula:

C(n,r)=n!/((n−r)!r!)

Combination: Picking a team of 3 people from a football coaching group of 10. C(10,3) = 10!(3!(10−3)!) = 120.

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Cocunut Development Board Cochi .
Command Area Devolopment Authority(CADA) Perukavu(Thrissur) .
Farm Information Bureau Kavadiyar .
KERAFED Thiruvananthapuram .
Kerala Agro Industries Corporation(KAMCO) Athani(Ernakulam) .
Kerala Livestock Development Corporation Pattom (Thiruvananthapuram) .
Kerala state Horti cultural Development Corporation Vellayambalam(Thiruvananthapuram) .
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Important UN Years are given below. 1972 പുസ്തക വർഷം.
1973 കോപ്പർനിക്കസ് വർഷം.
1974 ജനസംഖ്യാ വർഷം.
1975 വനിത വർഷം.
1985 യുവജന വർഷം.
1986 ലോക സമാധാനവർഷം.
1987 അഭയാർത്ഥി പാർപ്പിട വർഷം.
1988 എയ്ഡ്സ് വർഷം.
1992 ബഹിരാകാശ വർഷം.
1993 തദ്ദേശിയ ജനസംഖ്യ വർഷം.
1994 കുടുംബ വർഷം.
1995 സഹിഷ്ണുത വർഷം.
1998 സമുദ്ര വർഷം.
1999 വയോജന വർഷം.
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2001 സന്നദ്ധ സേവകാ വർഷം.
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Major Indian Authors and Languages

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Urdu : Ali Sardar Jafri, Asadullah Khan 'Ghalib', Mohammed Iqbal, Mir Taqi Mir, Raghupati Sahai 'Firaq Gorakhpuri', Kanwar Mohinder Singh Bedi, Faiz Ahmed 'Faiz', Krishan Chander, Rajinder Singh Bedi, Upendra Nath Ashq, Qurrtulain Haider.
Telugu : Ajanta, Lakshrni Narasimhan, Triputi, V. Satyanarayana. .
Tamil : P. V. Akilan, Subramania Bharati, Ramalingam, D. Jayakanthan. .
Sindhi : Ishwar Anchal, Hari Motwani, Mohan Kalpana. .
Sanskrit : Maharishi Valmiki, Maharishi Ved Vyas, Harsha, Ashvaghosh, Shudrak, Bhasa, Bharvi, Jaidev, Bhartrihari, Kalidas, Dandi, Banabhatta, Bhavabhuti, Shyam Dev Prashar, Kamlesh Dutta Tripathi, Ram Karan Sharma. .
Punjabi : Bhai Veer Singh, Dhani Ram Chatrik, Amrita Pritam, Jaswant Singh Kanwal, Nanak Singh, Balwant Gargi, Waris Shah, Bulle Shah, Sheikh Farid. .
Odia : Gopabandhu Das, Gopi Nath Mohanty, Pandit Dukhisyama Pattanayak, Radha Nath Ray, Satchidanand Routray, Si...

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