Q63.The Number of ways of choosing 10 objects out of 31 objects of which 10 are identical and the remaining 21 are distinct, is: (1) 220 (2) 221 (3) 220 + 1 (4) 220 - 1
What This Question Tests
This question requires calculating the number of ways to select a specific number of objects from a set containing both identical and distinct items, which involves summing binomial coefficients.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
Sum (from k=0 to m) of nCk when n is odd and m=(n-1)/2 is 2^(n-1)
📚 NCERT Sections This Tests
5.12 — Write All The Geometrical Isomers Of [Pt(Nh3)(Br)(Cl)(Py)] And How Many Of
Chemistry Class 11 · Chapter 5
5.12 Write all the geometrical isomers of [Pt(NH3)(Br)(Cl)(py)] and how many of these will exhibit optical isomers?
5.11 — Draw All The Isomers (Geometrical And Optical) Of:
Chemistry Class 11 · Chapter 5
5.11 Draw all the isomers (geometrical and optical) of: (i) [CoCl2(en)2] + (ii) [Co(NH3)Cl(en)2] 2+ (iii) [Co(NH3)2Cl2(en)]+
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
📋 Question Details
- Chapter
- Permutation & Combination
- Topic
- Combinations with identical and distinct objects
- Year
- 2019
- Shift
- 12 Apr Shift 1
- Q Number
- Q63
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
More from this Chapter
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