Greece trips

People travel to the seaside in Greece for 8-day, 10-day and 12-day stays. An assigned delegate flies there and back with each group of passengers. On May 1, all three groups and their delegates will fly to the sea simultaneously.
When will all three delegates meet again on one plane?

Final Answer:

t =  120 d

Step-by-step explanation:

$$\begin{gathered} 8=2^3 \\ 10=2\cdot 5 \\ 12=2^2\cdot 3 \\ LCM(8,10,12)=2^3\cdot 3\cdot 5=120 \\ t=LCM(8,10,12)=120\text{d} \end{gathered}$$

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