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There are 10 lamps in a hall. Each one of them can be switched on independently. Find the number of ways in which the hall can be illuminated. |
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Answer» There are 10 lamps in a hall. The hall can be illuminated if at least one lamp is switched. .'. Total number of ways = 10C1 + 10C2 + 10C3 … + 10C10 = 210 – 1 = 1024 - 1 = 1023 |
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