In the house of 9 floors and several entrances. on each floor in each stairwell on 4 apartments. on what floor apartment number 154 is?

In each stairwell on 36 apartments 9*4=36 154:36=4.2777777..... 36*4=144 apartments in 4 stairwell 154-144 =10 On the third floor would be (in the fifth stairwell) apartment number 154vrode on the 5th floor.
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