Three bells toll at intervals of 12 min, 24 min and 9 min respectively. If they toll togather at `11.00` a.m. then find the time at whcih they toll togather again for the first time. The Following are the steps involved in solving the above problem. Arrange them in the sequential order. (A) We know that the three bells toll togather at the multiples of LCM of 12 min, 24 min and 9 min. (B) After 11 a.m. they toll togather at (11 a.m.+ 72 min ) i.e., 12.12 p.m. (C) THe LCM of 12, 24 and 9 is 72. (D) Therefore, all the three bells toll togather for every 72 min.