Permutations & Combinations
Lift Problem — Exit at Different Floors
nta_pyq_2026_jan
Grade 11

Question:

Three persons enter a lift at the ground floor. The lift will go up to the 10th floor. The number of ways in which the three persons can exit the lift at three different floors, if the lift does not stop at the first, second and third floors, is equal to _____.

Step-by-Step Solution

Key Concept: Available floors: 4, 5, 6, 7, 8, 9, 10 (7 floors). Three persons exit at 3 different floors from these 7.
210 ways.
Correct Answer: 210

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