Ques. Four bells begin to toll together and then each one at intervals of 6 s, 7 s, 8 s and 9 s respectively. The number of times they will toll together in the next 2 hr is:
Op 1: 14 times
Op 2: 15 times
Op 3: 13 times
Op 4: 11 times
Op 5:
Correct Op : 1
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