At 3h00 a clock strikes the bell 3 times. The time between first and last strike is 30 seconds. How long does it take to strike the bell at 12h00?

1 answer

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notice there are only two time intervals between the first and third strike
so the time between strikes is 15 seconds

Thus at 12:00 we would have 11 time intervals, and it would take
11(15) or 165 seconds