Question 166873
We determine the LCM for the three beep rates and that's when they will beep together. The LCM for 8, 10 & 12 min is 120 min or two hours.  They beep together every two hours or at 5:00pm

CK
The 8 min beeper, beeps 15 times in 2 hours
@3:08-16-24-32-40-48-56-4:04-12-20-28-36-44-52-5:00
The 10 min beeper beeps 12 times in 2 hours
@3:10-20-30-40-50-4:00-10-20-30-40-50-5:00
The 12 min beeper beeps 10 times in 2 hours
@3:12-24-36-48-4:00-12-24-36-48-5:00


Hope this helps---ptaylor