3 lights started at the same time..1st blinks at 5 seconds, 2nd at 6 seconds and 3rd at 4 seconds...how often will they blink at the same time
To determine how often the three lights will blink at the same time, we can find the least common multiple (LCM) of the blinking intervals for each light.
The blinking intervals for the three lights are 5 seconds, 6 seconds, and 4 seconds, respectively.
To find the LCM, we can list the multiples of each number until we find a common multiple:
Multiples of 5: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50...
Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60...
Multiples of 4: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40...
From the lists above, we can see that the first common multiple is 30 seconds (the smallest number that is in all three lists). Therefore, the three lights will blink at the same time every 30 seconds.
So, the answer is: They will blink at the same time every 30 seconds.