Q63.A group of students comprises of 5 boys and n girls. If the number of ways, in which a team of 3 students can randomly be selected from this group such that there is at least one boy and at least one girl in each team, is 1750, then n is equal to (1) 24 (2) 27 (3) 25 (4) 28
What This Question Tests
This question tests the ability to apply combinations with the 'at least one' condition by summing up the ways for different valid selections of boys and girls to form an equation and solve for the unknown 'n'.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
๐ NCERT Sections This Tests
5.28 โ How Many Ions Are Produced From The Complex Co(Nh3)6Cl2 In Solution?
Chemistry Class 11 ยท Chapter 5
5.28 How many ions are produced from the complex Co(NH3)6Cl2 in solution? (i) 6 (ii) 4 (iii) 3 (iv) 2 139 Coordination Compounds Reprint 2025-26
5.15 โ Discuss The Nature Of Bonding In The Following Coordination Entities On The
Chemistry Class 11 ยท 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] 4โ (ii) [FeF6] 3โ (iii) [Co(C2O4)3]3โ (iv) [CoF6] 3โ
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?
๐ Question Details
- Chapter
- Permutation & Combination
- Topic
- Combination with constraints
- Year
- 2019
- Shift
- 12 Apr Shift 2
- Q Number
- Q63
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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