L.C.M. of 60 and 62 seconds is 1860 seconds1860/60 = 31 minutesThey will beep together at 10:31 a.m.Sometimes questions on red lights blinking comes in exam, which can be solved in the same way
Convert first all terms into cm.i.e. 1575 cm, 1125cm, 765cm.Now whenever we need to calculate this type of question, we need to find the HCF.HCF of above terms is 255.