- A16
- B12
- C8
- D6
Step-by-Step Solution
Enter: 4 ways. Leave by another door: 3 ways. . (16 allows leaving by the same door.)
Answer: B) 12
A hall has 4 doors. In how many ways can a person enter by one door and leave by a different door?
Competition practicePermutations & Combinations
Master this topic in 30 minutes a day.
Don't just memorise the answer — build a daily practice habit.
Practice 5 Similar Questions Free →All Permutations & Combinations practice questions
More Permutations & Combinations practice
Count all the different arrangements of the letters of the word KERALA.Digits may repeat. How many 3-digit numbers can be written using the digits 0 to 9?A quiz has 6 questions and each question has 4 options. If a student marks exactly one…From the letters of the word PLANETS, Gauri picks 2 vowels and 2 consonants (just a…No digit may repeat. How many odd 3-digit numbers can be formed using the digits 1 to 9?