Q71.The number of words (with or without meaning) that can be formed from all the letters of the word ′′LETTER′′ in which vowels never come together is.....
What This Question Tests
This problem assesses the ability to calculate permutations of letters with repetitions, specifically using the 'gaps' method to ensure certain letters (vowels) do not appear consecutively.
Concepts Tested
Formulas Used
n! / (p!q!...) for permutations
Gaps method
📚 NCERT Sections This Tests
1.1 — Define The Term Solution. How Many Types Of Solutions Are Formed? Write Briefly
Chemistry Class 11 · Chapter 1
1.1 Define the term solution. How many types of solutions are formed? Write briefly about each type with an example.
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
5.16 — Draw Figure To Show The Splitting Of D Orbitals In An Octahedral Crystal Field.
Chemistry Class 11 · Chapter 5
5.16 Draw figure to show the splitting of d orbitals in an octahedral crystal field.
📋 Question Details
- Chapter
- Permutation & Combination
- Topic
- Permutations with repetitions, "gaps" method
- Year
- 2020
- Shift
- 06 Sep Shift 2
- Q Number
- Q71
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
More from this Chapter
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