SOLUTION: a light flashes every 2 minutes, a second light flashes every 3.5 minutes, and 3 light flashes every 4 minutes. if all 3 light flash together at 8 pm, what is the next time of the

Question 793483: a light flashes every 2 minutes, a second light flashes every 3.5 minutes, and 3 light flashes every 4 minutes. if all 3 light flash together at 8 pm, what is the next time of the day they will flash together.
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
In order to sync up with the 3.5 flashes/min light,
this light must flash an even number of times, so the flashes occur
7, 14, 21, 28 etc. minutes after 8 PM
-------------------
The flash time of the 3.5/min light must also be a
multiple of 2/min, and 4/min in order to sync up
with these 2 lights
------------------

--------------
So, all the lights will flash together at 8:28 PM

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