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There are three traffic signals. Each signal changes colour from green to red and then from red to green. The first signal takes 25 seconds, the second signal takes 39 seconds and the third signal takes 60 seconds to change the colour from green to red. The lurations for green and red colours are same At 2:00 p.m, they together turn green. At what 2:00 pm, they together turn green. At what time will they change to green next, simultaneously?
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There are three traffic signals. Each signal changes colour from green...
Analysis:
Given durations for each traffic signal:
- Signal 1: 25 seconds
- Signal 2: 39 seconds
- Signal 3: 60 seconds
Let's find the time taken for all signals to go from green to red and back to green:
- Total time for Signal 1 = 25 + 25 = 50 seconds
- Total time for Signal 2 = 39 + 39 = 78 seconds
- Total time for Signal 3 = 60 + 60 = 120 seconds

Finding the LCM:
To find the time when all three signals will turn green simultaneously, we need to find the least common multiple (LCM) of the total times for each signal.
LCM of 50, 78, and 120 is 600 seconds.

Calculating the Next Simultaneous Green:
At 2:00 p.m., the signals turn green together. To find the next time they will simultaneously turn green, we need to add 600 seconds (LCM) to 2:00 p.m.
Adding 600 seconds to 2:00 p.m.:
- 600 seconds = 10 minutes
- 2:00 p.m. + 10 minutes = 2:10 p.m.
Therefore, the next time when all three signals will change to green simultaneously is at 2:10 p.m.
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There are three traffic signals. Each signal changes colour from green to red and then from red to green. The first signal takes 25 seconds, the second signal takes 39 seconds and the third signal takes 60 seconds to change the colour from green to red. The lurations for green and red colours are same At 2:00 p.m, they together turn green. At what 2:00 pm, they together turn green. At what time will they change to green next, simultaneously?
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