Q22.The number of natural numbers, between 212 and 999 , such that the sum of their digits is 15 , is
What This Question Tests
This question tests the ability to apply combinatorial reasoning to count three-digit numbers whose digits sum to a specific value, requiring careful casework and systematic enumeration.
Concepts Tested
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?
2.2 โ A Regular Hexagon Of Side 10 Cm Has A Charge 5 Mc At Each Of Its
Physics Class 11 ยท Chapter 2
2.2 A regular hexagon of side 10 cm has a charge 5 mC at each of its vertices. Calculate the potential at the centre of the hexagon.
9.15 โ Apply Mirror Equation And The Condition:
Physics Class 12 ยท Chapter 9
9.15 Apply mirror equation and the condition: (a) f < 0 (concave mirror); u < 0 (object on left) (b) f > 0; u < 0 (c) f > 0 (convex mirror) and u < 0 (d) f < 0 (concave mirror); f < u < 0 to deduce the desired result.
๐ Question Details
- Chapter
- Permutation & Combination
- Topic
- Counting techniques with digit restrictions
- Year
- 2025
- Shift
- 28 Jan Shift 2
- Q Number
- Q22
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutation & Combination
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