Q65.If nP r = nP r+1 and nCr = nCrโ1, then the value of r is equal to: (1) 1 (2) 4 (3) 2 (4) 3
What This Question Tests
This question tests the ability to apply the basic formulas for permutations and combinations and solve a system of equations.
Concepts Tested
Formulas Used
nP r = n!/(n-r)!
nCr = n!/(r!(n-r)!)
nCr = nC(n-r)
๐ NCERT Sections This Tests
1.3 โ Define The Following Terms:
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1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
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?
1.28 โ Calculate The Mass Percentage Of Aspirin (C9H8O4) In Acetonitrile (Ch3Cn) When
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1.28 Calculate the mass percentage of aspirin (C9H8O4) in acetonitrile (CH3CN) when 6.5 g of C9H8O4 is dissolved in 450 g of CH3CN.
๐ Question Details
- Chapter
- Permutation & Combination
- Topic
- Properties of Permutations and Combinations
- Year
- 2021
- Shift
- 25 Jul Shift 2
- Q Number
- Q65
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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