How many different arrangements of distinct books are possible on a shelf?
Answer and explanation
Correct answer: C. 5040
**
- Step 1: The number of distinct linear permutations of distinct objects on a shelf is given by .
- Step 2: Apply the factorial for : .
- Step 3: Multiplying out the factors gives different book arrangements.
Answer
5040.
Why not the others: '720' calculates , which is the formula for circular arrangements rather than a linear shelf; '42' calculates , permuting only of the books; '49' calculates , incorrectly assuming independent replacement choices without decrementing.
Practise more Permutations and combinations.
Free questions with an explanation for every one, and full timed JEE Main mock tests.
More Permutations and combinations questions
- In how many ways can a committee of be chosen from people?
- In how many ways can a committee of be chosen from people?
- In how many ways can a committee of be chosen from people?
- In how many ways can a committee of be chosen from people?
- In how many ways can a committee of be chosen from people?
- How many different arrangements of distinct books are possible on a shelf?