Q63.Suppose that 20 pillars of the same height have been erected along the boundary of circular stadium. If the top of each pillar has been connected by beams with the top of all its non-adjacent pillars, then the total number of beams is: (1) 170 (2) 180 (3) 210 (4) 190
What This Question Tests
This problem requires calculating the total number of possible connections (beams) between 20 pillars and then subtracting the connections between adjacent pillars.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
📚 NCERT Sections This Tests
12.1 — (A) No Different From
Physics Class 12 · Chapter 12
12.1 (a) No different from (b) Thomson’s model; Rutherford’s model (c) Rutherford’s model (d) Thomson’s model; Rutherford’s model (e) Both the models
5.18 — What Is Crystal Field Splitting Energy? How Does The Magnitude Of Do Decide
Chemistry Class 11 · Chapter 5
5.18 What is crystal field splitting energy? How does the magnitude of Do decide the actual configuration of d orbitals in a coordination entity?
5.15 — Discuss The Nature Of Bonding In The Following Coordination Entities On The
Chemistry Class 11 · Chapter 5
5.15 Discuss the nature of bonding in the following coordination entities on the basis of valence bond theory: (i) [Fe(CN)6] 4– (ii) [FeF6] 3– (iii) [Co(C2O4)3]3– (iv) [CoF6] 3–
📋 Question Details
- Chapter
- Permutation & Combination
- Topic
- Combinations
- Year
- 2019
- Shift
- 10 Apr Shift 2
- Q Number
- Q63
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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