Question

six Bells commence tolling together and toll at intervals of 2, 4, 6, 8, 10 and 12 seconds respectively. In 30 minutes how many time will they toll together

Answer 1

LCM of 2,4,6,8,10,12

= 720 seconds

720 / 60 = 12

it will toll together after 12 mins so in 30 mins it will toll 2 times

Answer 2

$((2 + 4 + 6 + 8 + 10 + 12) \div 6) \div 30$