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    Question

    Three bells ring at intervals of 28 seconds, 60 seconds,

    and 84 seconds, respectively. How many times will all three bells ring together in a span of 10 minutes?
    A 1 Correct Answer Incorrect Answer
    B 5 Correct Answer Incorrect Answer
    C 2 Correct Answer Incorrect Answer

    Solution

    Time taken by all 3 bells to ring together = L.C.M of 28, 60 and 84 = 420 seconds 10 minutes = 10 X 60 = 600 seconds 600 ÷ 420 ~ 1.42 So, the three bells will ring together only once in the given interval of 10 minutes.

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