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A lift carrying 50 passengers from the ground floor of a 100-storeyed building is moving upwards. The lift stops at the 1st, 2nd, and 3rd floor, then skips the 4th floor, again stops at the 5th, 6th, and 7th, then skips the 8th floor, and so on. Passengers get discharged in a pattern. 2, 3, 3, 2, 3, 3..... On which floor does the lift become empty?

Solution

✅ Correct Option: 1

The lift stops at floors: 1,2,31, 2, 3, skips 44, then 5,6,75, 6, 7, skips 88, then 9,10,119, 10, 11, skips 1212, and so on.

Pattern: Stop 33 floors → Skip 11 floor → Repeat

Passenger discharge pattern: 2,3,3,2,3,3,2,3,3...2, 3, 3, 2, 3, 3, 2, 3, 3... (repeats every 33 stops)


Tracking passengers remaining after each stop:

StopFloorDischargedRemaining
StartGround005050
1111224848
2222334545
3333334242
4455224040
5566333737
6677333434
7799223232
881010332929
991111332626
10101313222424
11111414332121
12121515331818
13131717221616
14141818331313
15151919331010
161621212288
171722223355
181823233322
191925252200

The lift becomes empty on floor 2525.

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