Question
Seven bells start tolling together. They toll at intervals of 3, 5, 7, 9, 12, 15 and 18 seconds respectively. How many times will all the bells toll together in 42 minutes ?
Asked in UP Police SI (दरोगा) · 2026
LCM and HCF · Quantitative Aptitude
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When quantities must be divided into groups of different specified sizes without leaving a remainder, look for a common multiple; if the least possible quantity is required, use the LCM.
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Questions Asked from LCM: Prime Factorisation & The Ladder Method in Previous Exams
See how often LCM: Prime Factorisation & The Ladder Method has appeared in previous-year questions across major government exams.
15UPSC Questions Asked in These Years:2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2022, 2023, 2024, 2026
9SSC Questions Asked in These Years:2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026
7Railways Questions Asked in These Years:2016, 2018, 2021, 2022, 2024, 2025, 2026
16State PSC Questions Asked in These Years:2002, 2004, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025
LCM: Prime Factorisation & The Ladder Method has appeared in 47 previous-year exam questions, most frequently in State PSC, UPSC and SSC.
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