SOLUTION: Two light house flash their lights every 20 seconds and 30 seconds respectively. Given that they flashed together at 8:00 P.M.. When will they next flash together?

Question 765931: Two light house flash their lights every 20 seconds and 30 seconds respectively. Given that they flashed together at 8:00 P.M.. When will they next flash together?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Find the smallest number that both
20 and 30 divide into evenly

but,

--------------
In 60 seconds, or 8:01 PM, they both
flash together

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