Five bells ring at intervals of 3 , 5 , 6 , 8 and 9 seconds respectively. If all the bells ring once together, after how long a period would the bells - Quantitative Aptitude MCQ Competitive Examination 2026 | ExamTest.live

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Five bells ring at intervals of 3, 5, 6, 8 and 9 seconds respectively. If all the bells ring once together, after how long a period would the bells ring together again?

Solution & Step-by-step Explanation

To find the time when they will ring together again, we need to find the Least Common Multiple (LCM) of the given intervals: 3, 5, 6, 8, 9 . Let's find the Prime Factorization: * 3 = 3^{1} * 5 = 5^{1} * 6 = 2^{1} \times 3^{1} * 8 = 2^{3} * 9 = 3^{2} LCM = 2^{3} \times 3^{2} \times 5^{1} = 8 \times 9 \times 5 = 360 seconds Convert seconds into minutes: Time = \frac{360}{60} = 6 minutes

Try it yourself before checking the explanation above.

Five bells ring at intervals of 3, 5, 6, 8 and 9 seconds respectively. If all the bells ring once together, after how long a period would the bells ring together again?

12 minutes

6 minutes

18 minutes

24 minutes

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