Tom and Amy set the alarms on their phones to sound at 6:45 am. Both alarms sound together at 6:45 am. Toms alarm sound every 9 minutes and Amy's alarm sounds every 12 minutes. At what time will both alarms next sound together?

Question

Mathematics

Elaine Savage

9 March, 02:48

Tom and Amy set the alarms on their phones to sound at 6:45 am. Both alarms sound together at 6:45 am. Toms alarm sound every 9 minutes and Amy's alarm sounds every 12 minutes. At what time will both alarms next sound together?

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Answers (2)

Know the Answer?

Zaiden · Answer 1

Answer is 7:21am,

12x3=36

9x4=36

Hence 6:45am adding 36 mins equals to 7:21am

Lilliana Sexton · Answer 2

After 36 min, first alarm will ring 4 times (36=4*9) and the second alarm 3 times (36=3*12)

6.45 - 6.54 - 7.03 - 7.12 - 7.21

6.45 - 6.57 - 7.09 - 7.21

At 7.21 will ring together