JEE Mains · Maths · STD 11 - 6. permutation and combination
Three persons enter in a lift at the ground floor. The lift will go up to \(10^{\text {th }}\) 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 first, second and third floors, is equal to ___ .
- A 210
- B 420
- C 105
- D 315
Answer & Solution
Correct Answer
(A) 210
Step-by-step Solution
Detailed explanation
\({ }^7 C _3 \times \lfloor 3\) = 210
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