Q82.A class contains b boys and g girls. If the number of ways of selecting 3 boys and 2 girls from the class is 168 , then b + 3g is equal to
What This Question Tests
This question tests the basic application of the combination formula (nCr) to form an equation and then solve for the unknown variables 'b' and 'g' by trial and error or factorization of 168.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
bC3 * gC2 = 168
๐ NCERT Sections This Tests
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๐ Question Details
- Chapter
- Permutation & Combination
- Topic
- Combinations (selections)
- Year
- 2022
- Shift
- 28 Jul Shift 2
- Q Number
- Q82
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
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