Q82.In an examination, 5 students have been allotted their seats as per their roll numbers. The number of ways, in which none of the students sits on the allotted seat, is
What This Question Tests
This problem directly tests the concept of derangements, which is the number of permutations where no element appears in its original position.
Concepts Tested
Formulas Used
D_n = n! [1/0! - 1/1! + 1/2! - ... + (-1)โฟ/n!]
๐ NCERT Sections This Tests
5.12 โ Write All The Geometrical Isomers Of [Pt(Nh3)(Br)(Cl)(Py)] And How Many Of
Chemistry Class 11 ยท Chapter 5
5.12 Write all the geometrical isomers of [Pt(NH3)(Br)(Cl)(py)] and how many of these will exhibit optical isomers?
5.16 โ Draw Figure To Show The Splitting Of D Orbitals In An Octahedral Crystal Field.
Chemistry Class 11 ยท Chapter 5
5.16 Draw figure to show the splitting of d orbitals in an octahedral crystal field.
14.2 โ Which Of The Statements Given In Exercise 14.1 Is True For P-Type
Physics Class 12 ยท Chapter 14
14.2 Which of the statements given in Exercise 14.1 is true for p-type semiconductos.
๐ Question Details
- Chapter
- Permutation & Combination
- Topic
- Derangements
- Year
- 2023
- Shift
- 11 Apr Shift 1
- Q Number
- Q82
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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