In the house of 10 floors and several entrances. On each floor on 4 apartment in each stairwell. On what floor there is apartment No. 157

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On the 10th floor there are 157 apartment. In each stairwell of 40 apartments. Therefore, in 4 stairwell there will be 160 apartments. The account of apartments begins with 1 floor. Since the last apartment (160) is in the 4th stairwell, it will be on the latest floor (10), and as, on each floor on 4 apartments, 157 apartment will be on the same floor, as well as apartment 160. — gt; 10th floor
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