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MathsHardNumerical2023 ยท 13 Apr Shift 1

Q62.The number of seven digit positive integers formed using the digits 1, 2, 3 and 4 only and sum of the digits equal to 12 is _______.

What This Question Tests

This problem requires finding the number of 7-digit integers formed by specific digits (1, 2, 3, 4) whose sum is 12, involving advanced combinatorial counting techniques like generating functions or casework.

Concepts Tested

CombinatoricsStars and bars method (or similar techniques for compositions)Digit problems

Formulas Used

Coefficient extraction from generating functions or direct counting

๐Ÿ“š NCERT Sections This Tests

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๐Ÿ“‹ Question Details

Chapter
Permutation & Combination
Topic
Number of integers with given digit sum
Year
2023
Shift
13 Apr Shift 1
Q Number
Q62
Type
Numerical
NCERT Ref
Class 11 Mathematics Ch 7: Permutations and Combinations

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