Q16 of 110 Page 53

If a clock strikes once at 1 o’clock, twice at 2 o’clock and so on, how many times will it strike in a day?


The clock strikes once at 1, twice at 2 ….so it strikes 12times at 12

In a day this striking from 1 to 12 happens twice.


No. of strikes in one turn from 1 to 12 = 1 + 2 + 3 + …..12


⇒ No. of strikes in one turn from 1 to 12 =


As the striking happens twice in a day,


Total number of strikes in a day = 78 × 2 = 156


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